Add a test for CSS variables

This will be necessary for supporting variables in animations.

.gitlab-ci/flatpak-build.sh

@@ -19,6 +19,7 @@ flatpak build ${builddir} meson \
                 --buildtype=debugoptimized \
                 -Dx11-backend=true \
                 -Dwayland-backend=true \
+                -Dvulkan=disabled \
                 -Dbuild-tests=false \
                 -Dbuild-testsuite=false \
                 -Dbuild-examples=false \

build-aux/flatpak/org.gtk.Demo4.json

@@ -185,6 +185,7 @@
             "builddir" : true,
             "config-opts" : [
                 "--libdir=/app/lib",
+                "-Dvulkan=disabled",
                 "-Dbuildtype=debugoptimized",
                 "-Ddemo-profile=devel"
             ],

build-aux/flatpak/org.gtk.IconBrowser4.json

@@ -114,6 +114,7 @@
             "builddir" : true,
             "config-opts" : [
                 "--libdir=/app/lib",
+                "-Dvulkan=disabled",
                 "-Dbuildtype=debugoptimized",
                 "-Ddemo-profile=devel"
             ],

build-aux/flatpak/org.gtk.WidgetFactory4.json

@@ -114,6 +114,7 @@
             "builddir" : true,
             "config-opts" : [
                 "--libdir=/app/lib",
+                "-Dvulkan=disabled",
                 "-Dbuildtype=debugoptimized",
                 "-Ddemo-profile=devel"
             ],
@@ -130,6 +131,7 @@
         "env" : {
             "DBUS_SESSION_BUS_ADDRESS" : "''",
             "GSK_RENDERER" : "opengl",
+            "GDK_DEBUG" : "vulkan-disable",
             "G_ENABLE_DEBUG" : "true"
         }
     }

build-aux/flatpak/org.gtk.gtk4.NodeEditor.json

@@ -114,6 +114,7 @@
             "builddir" : true,
             "config-opts" : [
                 "--libdir=/app/lib",
+                "-Dvulkan=disabled",
                 "-Dbuildtype=debugoptimized",
                 "-Ddemo-profile=devel"
             ],
@@ -130,6 +131,7 @@
         "env" : {
             "DBUS_SESSION_BUS_ADDRESS" : "''",
             "GSK_RENDERER" : "opengl",
+            "GDK_DEBUG" : "vulkan-disable",
             "G_ENABLE_DEBUG" : "true"
         }
     }

demos/gtk-demo/menus.ui

@@ -2,7 +2,7 @@
 <interface>
   <menu id="menubar">
     <submenu>
-      <attribute name="label" translatable="yes">_File</attribute>
+      <attribute name="label" translatable="yes">_Application</attribute>
       <section>
         <item>
           <attribute name="label" translatable="yes">_New</attribute>
@@ -33,7 +33,7 @@
       </section>
     </submenu>
     <submenu>
-      <attribute name="label" translatable="yes">_Preferences</attribute>
+      <attribute name="label" translatable="yes">_File</attribute>
       <section>
         <item>
           <attribute name="label" translatable="yes">_Prefer Dark Theme</attribute>

gdk/gdkdrag.c

@@ -50,6 +50,18 @@
 #include "gdkenumtypes.h"
 #include "gdkeventsprivate.h"
 
+static struct {
+  GdkDragAction action;
+  const char   *name;
+  GdkCursor    *cursor;
+} drag_cursors[] = {
+  { GDK_ACTION_ASK,     "dnd-ask",  NULL },
+  { GDK_ACTION_COPY,    "copy", NULL },
+  { GDK_ACTION_MOVE,    "move", NULL },
+  { GDK_ACTION_LINK,    "alias", NULL },
+  { 0,                  "no-drop", NULL },
+};
+
 enum {
   PROP_0,
   PROP_CONTENT,
@@ -774,20 +786,6 @@ gdk_drag_handle_source_event (GdkEvent *event)
   return FALSE;
 }
 
-static struct {
-  GdkDragAction action;
-  const char   *name;
-  GdkCursor    *cursor;
-} drag_cursors[] = {
-  { 0,               "default",  NULL },
-  { GDK_ACTION_ASK,  "dnd-ask",  NULL },
-  { GDK_ACTION_COPY, "copy",     NULL },
-  { GDK_ACTION_MOVE, "dnd-move", NULL }, /* Not using move here, since move is stuck using
-                                          * a mismatched visual metaphor in Adwaita
-                                          */
-  { GDK_ACTION_LINK, "alias",    NULL },
-};
-
 GdkCursor *
 gdk_drag_get_cursor (GdkDrag       *drag,
                      GdkDragAction  action)

gdk/loaders/gdkjpeg.c

@@ -30,7 +30,6 @@
 #include <jpeglib.h>
 #include <jerror.h>
 #include <setjmp.h>
-#include <malloc.h>
 
 /* {{{ Error handling */
 
@@ -238,10 +237,8 @@ gdk_load_jpeg (GBytes  *input_bytes,
 
   g_bytes_unref (bytes);
 
-  malloc_trim (0);
-
   gdk_profiler_end_mark (before, "Load jpeg", NULL);
-
+ 
   return texture;
 }
 

gdk/loaders/gdkpng.c

@@ -27,7 +27,6 @@
 #include "gsk/gl/fp16private.h"
 #include <png.h>
 #include <stdio.h>
-#include <malloc.h>
 
 /* The main difference between the png load/save code here and
  * gdk-pixbuf is that we can support loading 16-bit data in the
@@ -301,8 +300,6 @@ gdk_load_png (GBytes  *bytes,
   g_free (row_pointers);
   png_destroy_read_struct (&png, &info, NULL);
 
-  malloc_trim (0);
-
   if (GDK_PROFILER_IS_RUNNING)
     {
       gint64 end = GDK_PROFILER_CURRENT_TIME;

gdk/loaders/gdktiff.c

@@ -26,7 +26,6 @@
 #include "gdktexturedownloaderprivate.h"
 
 #include <tiffio.h>
-#include <malloc.h>
 
 /* Our main interest in tiff as an image format is that it is
  * flexible enough to save all our texture formats without
@@ -501,8 +500,6 @@ gdk_load_tiff (GBytes  *input_bytes,
 
   TIFFClose (tif);
 
-  malloc_trim (0);
-
   if (GDK_PROFILER_IS_RUNNING)
     {
       gint64 end = GDK_PROFILER_CURRENT_TIME;

gdk/macos/GdkMacosWindow.c

@@ -296,6 +296,10 @@ typedef NSString *CALayerContentsGravity;
   GdkMonitor *monitor;
   GdkRectangle geometry;
   GdkRectangle workarea;
+  int shadow_top = 0;
+  int shadow_left = 0;
+  int shadow_right = 0;
+  int shadow_bottom = 0;
   GdkRectangle window_gdk;
   GdkPoint pointer_position;
   GdkPoint new_origin;
@@ -303,6 +307,13 @@ typedef NSString *CALayerContentsGravity;
   if (!inManualMove)
     return NO;
 
+  /* Get our shadow so we can adjust the window position sans-shadow */
+  _gdk_macos_surface_get_shadow (gdk_surface,
+                                 &shadow_top,
+                                 &shadow_right,
+                                 &shadow_bottom,
+                                 &shadow_left);
+
   windowFrame = [self frame];
   currentLocation = [NSEvent mouseLocation];
 
@@ -328,9 +339,21 @@ typedef NSString *CALayerContentsGravity;
   window_gdk.width = windowFrame.size.width;
   window_gdk.height = windowFrame.size.height;
 
+  /* Subtract our shadowin from the window */
+  window_gdk.x += shadow_left;
+  window_gdk.y += shadow_top;
+  window_gdk.width = window_gdk.width - shadow_left - shadow_right;
+  window_gdk.height = window_gdk.height - shadow_top - shadow_bottom;
+
   /* Now place things on the monitor */
   _edge_snapping_motion (&self->snapping, &pointer_position, &window_gdk);
 
+  /* And add our shadow back to the frame */
+  window_gdk.x -= shadow_left;
+  window_gdk.y -= shadow_top;
+  window_gdk.width += shadow_left + shadow_right;
+  window_gdk.height += shadow_top + shadow_bottom;
+
   /* Convert to quartz coordinates */
   _gdk_macos_display_to_display_coords ([self gdkDisplay],
                                         window_gdk.x,
@@ -714,11 +737,17 @@ typedef NSString *CALayerContentsGravity;
 
 -(NSRect)constrainFrameRect:(NSRect)frameRect toScreen:(NSScreen *)screen
 {
+  GdkMacosSurface *surface = gdk_surface;
   NSRect rect;
+  int shadow_top;
 
+  /* Allow the window to move up "shadow_top" more than normally allowed
+   * by the default impl. This makes it possible to move windows with
+   * client side shadow right up to the screen's menu bar. */
+  _gdk_macos_surface_get_shadow (surface, &shadow_top, NULL, NULL, NULL);
   rect = [super constrainFrameRect:frameRect toScreen:screen];
   if (frameRect.origin.y > rect.origin.y)
-    rect.origin.y = MIN (frameRect.origin.y, rect.origin.y);
+    rect.origin.y = MIN (frameRect.origin.y, rect.origin.y + shadow_top);
 
   return rect;
 }

gdk/macos/gdkmacosdisplay-wm.c

@@ -47,20 +47,20 @@ _gdk_macos_display_position_toplevel_with_parent (GdkMacosDisplay *self,
   /* Try to center on top of the parent but also try to make the whole thing
    * visible in case that lands us under the topbar/panel/etc.
    */
-  parent_rect.x = parent->root_x;
-  parent_rect.y = parent->root_y;
-  parent_rect.width = GDK_SURFACE (parent)->width;
-  parent_rect.height = GDK_SURFACE (parent)->height;
+  parent_rect.x = parent->root_x + parent->shadow_left;
+  parent_rect.y = parent->root_y + parent->shadow_top;
+  parent_rect.width = GDK_SURFACE (parent)->width - parent->shadow_left - parent->shadow_right;
+  parent_rect.height = GDK_SURFACE (parent)->height - parent->shadow_top - parent->shadow_bottom;
 
-  surface_rect.width = GDK_SURFACE (surface)->width;
-  surface_rect.height = GDK_SURFACE (surface)->height;
+  surface_rect.width = GDK_SURFACE (surface)->width - surface->shadow_left - surface->shadow_right;
+  surface_rect.height = GDK_SURFACE (surface)->height - surface->shadow_top - surface->shadow_bottom;
   surface_rect.x = parent_rect.x + ((parent_rect.width - surface_rect.width) / 2);
   surface_rect.y = parent_rect.y + ((parent_rect.height - surface_rect.height) / 2);
 
   _gdk_macos_monitor_clamp (GDK_MACOS_MONITOR (monitor), &surface_rect);
 
-  *x = surface_rect.x;
-  *y = surface_rect.y;
+  *x = surface_rect.x - surface->shadow_left;
+  *y = surface_rect.y - surface->shadow_top;
 }
 
 static inline gboolean
@@ -99,15 +99,15 @@ _gdk_macos_display_position_toplevel (GdkMacosDisplay *self,
   gdk_macos_monitor_get_workarea (monitor, &workarea);
 
   /* First place at top-left of current monitor */
-  surface_rect.width = GDK_SURFACE (surface)->width;
-  surface_rect.height = GDK_SURFACE (surface)->height;
+  surface_rect.width = GDK_SURFACE (surface)->width - surface->shadow_left - surface->shadow_right;
+  surface_rect.height = GDK_SURFACE (surface)->height - surface->shadow_top - surface->shadow_bottom;
   surface_rect.x = workarea.x + ((workarea.width - surface_rect.width) / 2);
   surface_rect.y = workarea.y + ((workarea.height - surface_rect.height) / 2);
 
   _gdk_macos_monitor_clamp (GDK_MACOS_MONITOR (surface->best_monitor), &surface_rect);
 
-  *x = surface_rect.x;
-  *y = surface_rect.y;
+  *x = surface_rect.x - surface->shadow_left;
+  *y = surface_rect.y - surface->shadow_top;
 
   /* Try to see if there are any other surfaces at this origin and if so,
    * adjust until we get something better.
@@ -119,11 +119,11 @@ _gdk_macos_display_position_toplevel (GdkMacosDisplay *self,
       *y += WARP_OFFSET_Y;
 
       /* If we reached the bottom right, just bail and try the workspace origin */
-      if (*x + WARP_OFFSET_X > workarea.x + workarea.width ||
-          *y + WARP_OFFSET_Y > workarea.y + workarea.height)
+      if (*x + surface->shadow_left + WARP_OFFSET_X > workarea.x + workarea.width ||
+          *y + surface->shadow_top + WARP_OFFSET_Y > workarea.y + workarea.height)
         {
-          *x = workarea.x;
-          *y = workarea.y;
+          *x = workarea.x - surface->shadow_left;
+          *y = workarea.y - surface->shadow_top;
           return;
         }
     }

gdk/macos/gdkmacospopupsurface.c

@@ -68,10 +68,19 @@ gdk_macos_popup_surface_layout (GdkMacosPopupSurface *self,
     monitor = _gdk_macos_surface_get_best_monitor (GDK_MACOS_SURFACE (self));
   gdk_macos_monitor_get_workarea (monitor, &bounds);
 
+  gdk_popup_layout_get_shadow_width (layout,
+                                     &self->parent_instance.shadow_left,
+                                     &self->parent_instance.shadow_right,
+                                     &self->parent_instance.shadow_top,
+                                     &self->parent_instance.shadow_bottom);
+
   gdk_surface_layout_popup_helper (GDK_SURFACE (self),
                                    width,
                                    height,
-                                   0, 0, 0, 0, /* shadow-left/right/top/bottom */
+                                   self->parent_instance.shadow_left,
+                                   self->parent_instance.shadow_right,
+                                   self->parent_instance.shadow_top,
+                                   self->parent_instance.shadow_bottom,
                                    monitor,
                                    &bounds,
                                    self->layout,

gdk/macos/gdkmacossurface-private.h

@@ -61,6 +61,11 @@ struct _GdkMacosSurface
     int height;
   } next_layout;
 
+  int shadow_top;
+  int shadow_right;
+  int shadow_bottom;
+  int shadow_left;
+
   cairo_rectangle_int_t next_frame;
 
   gint64 pending_frame_counter;
@@ -86,6 +91,16 @@ CGDirectDisplayID  _gdk_macos_surface_get_screen_id           (GdkMacosSurface
 const char        *_gdk_macos_surface_get_title               (GdkMacosSurface      *self);
 void               _gdk_macos_surface_set_title               (GdkMacosSurface      *self,
                                                                const char           *title);
+void               _gdk_macos_surface_get_shadow              (GdkMacosSurface      *self,
+                                                               int                  *top,
+                                                               int                  *right,
+                                                               int                  *bottom,
+                                                               int                  *left);
+void               _gdk_macos_surface_set_shadow              (GdkMacosSurface      *self,
+                                                               int                   top,
+                                                               int                   right,
+                                                               int                   bottom,
+                                                               int                   left);
 gboolean           _gdk_macos_surface_is_opaque               (GdkMacosSurface      *self);
 NSView            *_gdk_macos_surface_get_view                (GdkMacosSurface      *self);
 gboolean           _gdk_macos_surface_get_modal_hint          (GdkMacosSurface      *self);

gdk/macos/gdkmacossurface.c

@@ -236,6 +236,32 @@ gdk_macos_surface_get_scale (GdkSurface *surface)
   return [self->window backingScaleFactor];
 }
 
+void
+_gdk_macos_surface_set_shadow (GdkMacosSurface *surface,
+                               int              top,
+                               int              right,
+                               int              bottom,
+                               int              left)
+{
+  GdkMacosSurface *self = (GdkMacosSurface *)surface;
+
+  g_assert (GDK_IS_MACOS_SURFACE (self));
+
+  if (self->shadow_top == top &&
+      self->shadow_right == right &&
+      self->shadow_bottom == bottom &&
+      self->shadow_left == left)
+    return;
+
+  self->shadow_top = top;
+  self->shadow_right = right;
+  self->shadow_bottom = bottom;
+  self->shadow_left = left;
+
+  if (top || right || bottom || left)
+    [self->window setHasShadow:NO];
+}
+
 static void
 gdk_macos_surface_begin_frame (GdkMacosSurface *self)
 {
@@ -553,6 +579,29 @@ gdk_macos_surface_init (GdkMacosSurface *self)
   self->monitors = g_ptr_array_new_with_free_func (g_object_unref);
 }
 
+void
+_gdk_macos_surface_get_shadow (GdkMacosSurface *self,
+                               int             *top,
+                               int             *right,
+                               int             *bottom,
+                               int             *left)
+{
+
+  g_return_if_fail (GDK_IS_MACOS_SURFACE (self));
+
+  if (top)
+    *top = self->shadow_top;
+
+  if (left)
+    *left = self->shadow_left;
+
+  if (bottom)
+    *bottom = self->shadow_bottom;
+
+  if (right)
+    *right = self->shadow_right;
+}
+
 gboolean
 _gdk_macos_surface_is_opaque (GdkMacosSurface *self)
 {
@@ -1048,12 +1097,16 @@ _gdk_macos_surface_monitor_changed (GdkMacosSurface *self)
 
           g_set_object (&child->best_monitor, best);
 
-          area.x = self->root_x + GDK_SURFACE (child)->x;
-          area.y = self->root_y + GDK_SURFACE (child)->y;
-          area.width = GDK_SURFACE (child)->width;
-          area.height = GDK_SURFACE (child)->height;
+          area.x = self->root_x + GDK_SURFACE (child)->x + child->shadow_left;
+          area.y = self->root_y + GDK_SURFACE (child)->y + child->shadow_top;
+          area.width = GDK_SURFACE (child)->width - child->shadow_left - child->shadow_right;
+          area.height = GDK_SURFACE (child)->height - child->shadow_top - child->shadow_bottom;
 
           _gdk_macos_monitor_clamp (GDK_MACOS_MONITOR (best), &area);
+
+          area.x -= child->shadow_left;
+          area.y -= child->shadow_top;
+
           _gdk_macos_surface_move (child, area.x, area.y);
           gdk_surface_invalidate_rect (GDK_SURFACE (child), NULL);
         }

gdk/macos/gdkmacostoplevelsurface.c

@@ -152,6 +152,13 @@ _gdk_macos_toplevel_surface_compute_size (GdkSurface *surface)
       mask = GDK_HINT_MIN_SIZE | GDK_HINT_MAX_SIZE;
     }
 
+  if (size.shadow.is_valid)
+    _gdk_macos_surface_set_shadow (macos_surface,
+                                   size.shadow.top,
+                                   size.shadow.right,
+                                   size.shadow.bottom,
+                                   size.shadow.left);
+
   _gdk_macos_surface_set_geometry_hints (macos_surface, &geometry, mask);
 
   if (surface->state & (GDK_TOPLEVEL_STATE_FULLSCREEN |

gdk/wayland/gdkcursor-wayland.c

@@ -79,7 +79,6 @@ static const struct {
   { "move",         "dnd-move" },
   { "no-drop",      "dnd-none" },
   { "dnd-ask",      "dnd-copy" }, /* not CSS, but we want to guarantee it anyway */
-  { "dnd-move",     "default" },
   { "not-allowed",  "crossed_circle" },
   { "grab",         "hand2" },
   { "grabbing",     "hand2" },

gdk/wayland/gdkdevice-wayland.c

@@ -310,8 +310,7 @@ gdk_wayland_device_update_surface_cursor (GdkDevice *device)
   if (buffer)
     {
       wl_surface_attach (pointer->pointer_surface, buffer, 0, 0);
-      if (wl_surface_get_version (pointer->pointer_surface) >= WL_SURFACE_SET_BUFFER_SCALE_SINCE_VERSION)
-        wl_surface_set_buffer_scale (pointer->pointer_surface, scale);
+      wl_surface_set_buffer_scale (pointer->pointer_surface, scale);
       wl_surface_damage (pointer->pointer_surface,  0, 0, w, h);
       wl_surface_commit (pointer->pointer_surface);
     }

gdk/wayland/gdkdisplay-wayland.c

@@ -58,7 +58,6 @@
 #include <wayland/xdg-foreign-unstable-v2-client-protocol.h>
 #include <wayland/server-decoration-client-protocol.h>
 #include "linux-dmabuf-unstable-v1-client-protocol.h"
-#include "presentation-time-client-protocol.h"
 
 #include "wm-button-layout-translation.h"
 
@@ -96,6 +95,7 @@
 #define GTK_SHELL1_VERSION       5
 #define OUTPUT_VERSION_WITH_DONE 2
 #define NO_XDG_OUTPUT_DONE_SINCE_VERSION 3
+#define XDG_ACTIVATION_VERSION   1
 #define OUTPUT_VERSION           3
 
 #ifdef HAVE_TOPLEVEL_STATE_SUSPENDED
@@ -585,25 +585,21 @@ gdk_registry_handle_global (void               *data,
     {
       display_wayland->xdg_activation =
         wl_registry_bind (display_wayland->wl_registry, id,
-                          &xdg_activation_v1_interface, 1);
+                          &xdg_activation_v1_interface,
+                          MIN (version, XDG_ACTIVATION_VERSION));
     }
   else if (strcmp (interface, "wp_fractional_scale_manager_v1") == 0)
     {
       display_wayland->fractional_scale =
         wl_registry_bind (display_wayland->wl_registry, id,
-                          &wp_fractional_scale_manager_v1_interface, 1);
+                          &wp_fractional_scale_manager_v1_interface,
+                          MIN (version, 1));
     }
   else if (strcmp (interface, "wp_viewporter") == 0)
     {
       display_wayland->viewporter =
         wl_registry_bind (display_wayland->wl_registry, id,
-                          &wp_viewporter_interface, 1);
-    }
-  else if (strcmp (interface, "wp_presentation") == 0)
-    {
-      display_wayland->presentation =
-        wl_registry_bind (display_wayland->wl_registry, id,
-                          &wp_presentation_interface,
+                          &wp_viewporter_interface,
                           MIN (version, 1));
     }
 
@@ -704,8 +700,7 @@ _gdk_wayland_display_open (const char *display_name)
   process_on_globals_closures (display_wayland);
 
   /* Wait for initializing to complete. This means waiting for all
-   * asynchronous roundtrips that were triggered during initial roundtrip.
-   */
+   * asynchronous roundtrips that were triggered during initial roundtrip. */
   while (display_wayland->async_roundtrips != NULL)
     {
       if (wl_display_dispatch (display_wayland->wl_display) < 0)
@@ -715,18 +710,6 @@ _gdk_wayland_display_open (const char *display_name)
         }
     }
 
-  /* Check that we got all the required globals */
-  if (display_wayland->compositor == NULL ||
-      display_wayland->shm == NULL ||
-      display_wayland->data_device_manager == NULL)
-    {
-      g_warning ("The Wayland compositor does not provide one or more of the required interfaces, "
-                 "not using Wayland display");
-      g_object_unref (display);
-
-      return NULL;
-    }
-
   if (display_wayland->xdg_wm_base_id)
     {
       display_wayland->shell_variant = GDK_WAYLAND_SHELL_VARIANT_XDG_SHELL;
@@ -816,7 +799,6 @@ gdk_wayland_display_dispose (GObject *object)
   g_clear_pointer (&display_wayland->xdg_activation, xdg_activation_v1_destroy);
   g_clear_pointer (&display_wayland->fractional_scale, wp_fractional_scale_manager_v1_destroy);
   g_clear_pointer (&display_wayland->viewporter, wp_viewporter_destroy);
-  g_clear_pointer (&display_wayland->presentation, wp_presentation_destroy);
   g_clear_pointer (&display_wayland->linux_dmabuf, zwp_linux_dmabuf_v1_destroy);
   g_clear_pointer (&display_wayland->linux_dmabuf_feedback, zwp_linux_dmabuf_feedback_v1_destroy);
   if (display_wayland->linux_dmabuf_formats)

gdk/wayland/gdkdisplay-wayland.h

@@ -39,7 +39,6 @@
 #include <gdk/wayland/xdg-activation-v1-client-protocol.h>
 #include <gdk/wayland/fractional-scale-v1-client-protocol.h>
 #include <gdk/wayland/viewporter-client-protocol.h>
-#include <gdk/wayland/presentation-time-client-protocol.h>
 
 #include <glib.h>
 #include <gdk/gdkkeys.h>
@@ -126,7 +125,6 @@ struct _GdkWaylandDisplay
   struct xdg_activation_v1 *xdg_activation;
   struct wp_fractional_scale_manager_v1 *fractional_scale;
   struct wp_viewporter *viewporter;
-  struct wp_presentation *presentation;
 
   GList *async_roundtrips;
 

gdk/wayland/gdkprivate-wayland.h

@@ -34,7 +34,6 @@
 #include <gdk/wayland/gdkwayland.h>
 #include <gdk/wayland/gdkdisplay-wayland.h>
 #include <gdk/wayland/gdkseat-wayland.h>
-#include <gdk/wayland/gdkwaylandpresentationtime-private.h>
 
 #include <xkbcommon/xkbcommon.h>
 

gdk/wayland/gdksubsurface-wayland.c

@@ -466,9 +466,9 @@ gdk_wayland_surface_create_subsurface (GdkSurface *surface)
   GdkWaylandSubsurface *sub;
   struct wl_region *region;
 
-  if (disp->subcompositor == NULL || disp->viewporter == NULL)
+  if (disp->viewporter == NULL)
     {
-      GDK_DISPLAY_DEBUG (display, OFFLOAD, "Can't use subsurfaces without subcompositor and viewporter");
+      GDK_DISPLAY_DEBUG (display, OFFLOAD, "Can't use subsurfaces without viewporter");
       return NULL;
     }
 

gdk/wayland/gdksurface-wayland-private.h

@@ -44,8 +44,6 @@ struct _GdkWaylandSurface
   struct wl_event_queue *event_queue;
   struct wl_callback *frame_callback;
 
-  GdkWaylandPresentationTime *presentation_time;
-
   unsigned int initial_configure_received : 1;
   unsigned int has_uncommitted_ack_configure : 1;
   unsigned int has_pending_subsurface_commits : 1;

gdk/wayland/gdksurface-wayland.c

@@ -52,7 +52,6 @@
 #include "gdktoplevel-wayland-private.h"
 
 #include "linux-dmabuf-unstable-v1-client-protocol.h"
-#include "presentation-time-client-protocol.h"
 
 
 /**
@@ -404,17 +403,6 @@ gdk_wayland_surface_request_frame (GdkSurface *surface)
   wl_proxy_set_queue ((struct wl_proxy *) self->frame_callback, NULL);
   wl_callback_add_listener (self->frame_callback, &frame_listener, surface);
 
-  if (self->presentation_time == NULL)
-    {
-      GdkWaylandDisplay *wayland_display = GDK_WAYLAND_DISPLAY (gdk_surface_get_display (surface));
-      self->presentation_time = gdk_wayland_presentation_time_new (wayland_display);
-    }
-
-  gdk_wayland_presentation_time_track (self->presentation_time,
-                                       clock,
-                                       self->display_server.wl_surface,
-                                       gdk_frame_clock_get_frame_counter (clock));
-
   for (gsize i = 0; i < gdk_surface_get_n_subsurfaces (surface); i++)
     {
       GdkSubsurface *subsurface = gdk_surface_get_subsurface (surface, i);
@@ -1060,7 +1048,6 @@ gdk_wayland_surface_hide_surface (GdkSurface *surface)
 
   unmap_popups_for_surface (surface);
 
-  g_clear_pointer (&impl->presentation_time, gdk_wayland_presentation_time_free);
   g_clear_pointer (&impl->frame_callback, wl_callback_destroy);
   if (impl->awaiting_frame_frozen)
     {

gdk/wayland/gdktoplevel-wayland.c

@@ -34,7 +34,6 @@
 #include "gdktoplevelprivate.h"
 #include "gdkdevice-wayland-private.h"
 
-#include <wayland/presentation-time-client-protocol.h>
 #include <wayland/xdg-shell-unstable-v6-client-protocol.h>
 #include <wayland/xdg-foreign-unstable-v2-client-protocol.h>
 
@@ -123,8 +122,6 @@ struct _GdkWaylandToplevel
 
   struct wl_output *initial_fullscreen_output;
 
-  struct wp_presentation_feedback *feedback;
-
   struct {
     GdkToplevelState unset_flags;
     GdkToplevelState set_flags;

gdk/wayland/gdkwaylandpresentationtime-private.h

@@ -1,19 +0,0 @@
-#pragma once
-
-#include <gdk/gdkframeclock.h>
-#include <gdk/wayland/gdkdisplay-wayland.h>
-#include <gdk/wayland/gdksurface-wayland.h>
-#include <gdk/wayland/gdkwaylanddisplay.h>
-
-G_BEGIN_DECLS
-
-typedef struct _GdkWaylandPresentationTime GdkWaylandPresentationTime;
-
-GdkWaylandPresentationTime *gdk_wayland_presentation_time_new   (GdkWaylandDisplay          *display);
-void                        gdk_wayland_presentation_time_track (GdkWaylandPresentationTime *self,
-                                                                 GdkFrameClock              *frame_clock,
-                                                                 struct wl_surface          *surface,
-                                                                 gint64                      frame_number);
-void                        gdk_wayland_presentation_time_free  (GdkWaylandPresentationTime *self);
-
-G_END_DECLS

gdk/wayland/gdkwaylandpresentationtime.c

@@ -1,152 +0,0 @@
-#include "config.h"
-
-#include <gdk/gdkframeclockprivate.h>
-
-#include "gdkwaylandpresentationtime-private.h"
-
-typedef struct _GdkWaylandPresentationFrame
-{
-  GdkWaylandPresentationTime *self;
-  struct wp_presentation_feedback *feedback;
-  GdkFrameClock *frame_clock;
-  gint64 frame_number;
-} GdkWaylandPresentationFrame;
-
-static void
-gdk_wayland_presentation_frame_free (GdkWaylandPresentationFrame *frame)
-{
-  g_clear_pointer (&frame->feedback, wp_presentation_feedback_destroy);
-  g_clear_object (&frame->frame_clock);
-  frame->self = NULL;
-  g_free (frame);
-}
-
-struct _GdkWaylandPresentationTime
-{
-  GdkWaylandDisplay *display;
-  GPtrArray *frames;
-};
-
-GdkWaylandPresentationTime *
-gdk_wayland_presentation_time_new (GdkWaylandDisplay *display)
-{
-  GdkWaylandPresentationTime *self;
-
-  g_return_val_if_fail (GDK_IS_WAYLAND_DISPLAY (display), NULL);
-
-  self = g_new0 (GdkWaylandPresentationTime, 1);
-  self->display = g_object_ref (display);
-  self->frames = g_ptr_array_new_with_free_func ((GDestroyNotify)gdk_wayland_presentation_frame_free);
-
-  return self;
-}
-
-void
-gdk_wayland_presentation_time_free (GdkWaylandPresentationTime *self)
-{
-  g_clear_pointer (&self->frames, g_ptr_array_unref);
-  g_clear_object (&self->display);
-  g_free (self);
-}
-
-static gint64
-time_from_wayland (uint32_t tv_sec_hi,
-                   uint32_t tv_sec_lo,
-                   uint32_t tv_nsec)
-{
-  guint64 t = tv_sec_hi;
-  t <<= 32;
-  t |= tv_sec_lo;
-  t *= G_USEC_PER_SEC;
-  t += tv_nsec / 1000L;
-  return (gint64)t;
-}
-
-static void
-gdk_wayland_presentation_feedback_sync_output (void                            *data,
-                                               struct wp_presentation_feedback *feedback,
-                                               struct wl_output                *output)
-{
-}
-
-static void
-gdk_wayland_presentation_feedback_presented (void                            *data,
-                                             struct wp_presentation_feedback *feedback,
-                                             uint32_t                         tv_sec_hi,
-                                             uint32_t                         tv_sec_lo,
-                                             uint32_t                         tv_nsec,
-                                             uint32_t                         refresh,
-                                             uint32_t                         seq_hi,
-                                             uint32_t                         seq_lo,
-                                             uint32_t                         flags)
-{
-  GdkWaylandPresentationFrame *frame = data;
-  GdkWaylandPresentationTime *self;
-  GdkFrameTimings *timings;
-  guint pos;
-
-  g_assert (frame != NULL);
-  g_assert (frame->self != NULL);
-
-  self = frame->self;
-
-  if ((timings = gdk_frame_clock_get_timings (frame->frame_clock, frame->frame_number)))
-    {
-      timings->presentation_time = time_from_wayland (tv_sec_hi, tv_sec_lo, tv_nsec);
-      timings->complete = TRUE;
-    }
-
-  if (g_ptr_array_find (self->frames, frame, &pos))
-    g_ptr_array_remove_index_fast (self->frames, pos);
-}
-
-static void
-gdk_wayland_presentation_feedback_discarded (void                            *data,
-                                             struct wp_presentation_feedback *feedback)
-{
-  GdkWaylandPresentationFrame *frame = data;
-  guint pos;
-
-  g_assert (frame != NULL);
-  g_assert (frame->self != NULL);
-
-  if (g_ptr_array_find (frame->self->frames, frame, &pos))
-    g_ptr_array_remove_index_fast (frame->self->frames, pos);
-}
-
-static const struct wp_presentation_feedback_listener gdk_wayland_presentation_feedback_listener = {
-  gdk_wayland_presentation_feedback_sync_output,
-  gdk_wayland_presentation_feedback_presented,
-  gdk_wayland_presentation_feedback_discarded,
-};
-
-void
-gdk_wayland_presentation_time_track (GdkWaylandPresentationTime *self,
-                                     GdkFrameClock              *frame_clock,
-                                     struct wl_surface          *surface,
-                                     gint64                      frame_number)
-{
-  struct wp_presentation_feedback *feedback;
-  GdkWaylandPresentationFrame *frame;
-
-  g_return_if_fail (self != NULL);
-  g_return_if_fail (surface != NULL);
-
-  if (self->display->presentation == NULL)
-    return;
-
-  if (!(feedback = wp_presentation_feedback (self->display->presentation, surface)))
-    return;
-
-  frame = g_new0 (GdkWaylandPresentationFrame, 1);
-  frame->self = self;
-  frame->frame_clock = g_object_ref (frame_clock);
-  frame->frame_number = frame_number;
-  frame->feedback = g_steal_pointer (&feedback);
-
-  g_ptr_array_add (self->frames, frame);
-
-  wp_presentation_feedback_add_listener (frame->feedback,
-                                         &gdk_wayland_presentation_feedback_listener,
-                                         frame);
-}

gdk/wayland/meson.build

@@ -22,7 +22,6 @@ gdk_wayland_sources = files([
   'gdktoplevel-wayland.c',
   'gdkpopup-wayland.c',
   'gdkvulkancontext-wayland.c',
-  'gdkwaylandpresentationtime.c',
   'wm-button-layout-translation.c',
 ])
 
@@ -70,7 +69,6 @@ proto_sources = [
   ['xdg-activation', 'staging', 'v1', ],
   ['fractional-scale', 'staging', 'v1', ],
   ['linux-dmabuf', 'unstable', 'v1', ],
-  ['presentation-time', 'stable', 'v1', ],
 ]
 
 gdk_wayland_gen_headers = []

gdk/win32/gdksurface-win32.c

@@ -1627,7 +1627,7 @@ _gdk_win32_surface_lacks_wm_decorations (GdkSurface *window)
   has_any_decorations = FALSE;
 
   if (style & (WS_BORDER | WS_THICKFRAME | WS_CAPTION |
-               WS_SYSMENU | WS_MAXIMIZEBOX))
+               WS_SYSMENU | WS_MINIMIZEBOX | WS_MAXIMIZEBOX))
     has_any_decorations = TRUE;
   else
     GDK_NOTE (MISC, g_print ("Window %p (handle %p): has no decorations (style %lx)\n",
@@ -1696,6 +1696,7 @@ _gdk_win32_surface_update_style_bits (GdkSurface *window)
       update_single_bit (&new_style, all, decorations & GDK_DECOR_RESIZEH, WS_THICKFRAME);
       update_single_bit (&new_style, all, decorations & GDK_DECOR_TITLE, WS_CAPTION);
       update_single_bit (&new_style, all, decorations & GDK_DECOR_MENU, WS_SYSMENU);
+      update_single_bit (&new_style, all, decorations & GDK_DECOR_MINIMIZE, WS_MINIMIZEBOX);
       update_single_bit (&new_style, all, decorations & GDK_DECOR_MAXIMIZE, WS_MAXIMIZEBOX);
     }
 

gsk/gl/gskglrenderjob.c

@@ -52,6 +52,8 @@
 #include "ninesliceprivate.h"
 #include "fp16private.h"
 
+#define ALLOW_OFFLOAD_FOR_ANY_TEXTURE 1
+
 #define ORTHO_NEAR_PLANE   -10000
 #define ORTHO_FAR_PLANE     10000
 #define MAX_GRADIENT_STOPS  6
@@ -174,8 +176,6 @@ struct _GskGLRenderJob
    * looking at the format of the framebuffer we are rendering on.
    */
   int target_format;
-
-  guint offscreen_count; /* if > 0, we're rendering to an offscreen */
 };
 
 typedef struct _GskGLRenderOffscreen
@@ -4002,15 +4002,9 @@ gsk_gl_render_job_visit_subsurface_node (GskGLRenderJob      *job,
     {
       if (!gdk_subsurface_is_above_parent (subsurface))
         {
-          if (job->offscreen_count > 0)
+          /* Clear the area so we can see through */
+          if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, color)))
             {
-              GDK_DISPLAY_DEBUG (gdk_gl_context_get_display (job->command_queue->context), OFFLOAD, "Hiding subsurface %p in offscreen context", subsurface);
-              gdk_subsurface_detach (subsurface);
-              gsk_gl_render_job_visit_node (job, gsk_subsurface_node_get_child (node));
-            }
-          else if (gsk_gl_render_job_begin_draw (job, CHOOSE_PROGRAM (job, color)))
-            {
-              /* Clear the area so we can see through */
               GskGLCommandBatch *batch;
               guint16 color[4];
               rgba_to_half (&(GdkRGBA){0,0,0,0}, color);
@@ -4428,12 +4422,8 @@ gsk_gl_render_job_visit_node_with_offscreen (GskGLRenderJob       *job,
       reset_clip = TRUE;
     }
 
-  job->offscreen_count++;
-
   gsk_gl_render_job_visit_node (job, node);
 
-  job->offscreen_count--;
-
   if (reset_clip)
     gsk_gl_render_job_pop_clip (job);
 

gtk/css/gtkcssparser.c

@@ -27,12 +27,13 @@
 #include "gtkcsslocationprivate.h"
 
 typedef struct _GtkCssParserBlock GtkCssParserBlock;
+typedef struct _GtkCssParserTokenStreamData GtkCssParserTokenStreamData;
 
 struct _GtkCssParser
 {
   volatile int ref_count;
 
-  GtkCssTokenizer *tokenizer;
+  GPtrArray *tokenizers;
   GFile *file;
   GFile *directory;
   GtkCssParserErrorFunc error_func;
@@ -42,6 +43,11 @@ struct _GtkCssParser
   GArray *blocks;
   GtkCssLocation location;
   GtkCssToken token;
+
+  GtkCssVariableValue **refs;
+  gsize n_refs;
+  gsize next_ref;
+  gboolean var_fallback;
 };
 
 struct _GtkCssParserBlock
@@ -52,6 +58,12 @@ struct _GtkCssParserBlock
   GtkCssTokenType alternative_token;
 };
 
+static inline GtkCssTokenizer *
+get_tokenizer (GtkCssParser *self)
+{
+  return g_ptr_array_index (self->tokenizers, self->tokenizers->len - 1);
+}
+
 static GtkCssParser *
 gtk_css_parser_new (GtkCssTokenizer       *tokenizer,
                     GFile                 *file,
@@ -64,7 +76,11 @@ gtk_css_parser_new (GtkCssTokenizer       *tokenizer,
   self = g_new0 (GtkCssParser, 1);
 
   self->ref_count = 1;
-  self->tokenizer = gtk_css_tokenizer_ref (tokenizer);
+
+  self->tokenizers = g_ptr_array_new ();
+  g_ptr_array_add (self->tokenizers, gtk_css_tokenizer_ref (tokenizer));
+  g_ptr_array_set_free_func (self->tokenizers, (GDestroyNotify) gtk_css_tokenizer_unref);
+
   if (file)
     {
       self->file = g_object_ref (file);
@@ -117,19 +133,46 @@ gtk_css_parser_new_for_bytes (GBytes                *bytes,
   return result;
 }
 
+GtkCssParser *
+gtk_css_parser_new_for_token_stream (GtkCssVariableValue    *value,
+                                     GFile                  *file,
+                                     GtkCssVariableValue   **refs,
+                                     gsize                   n_refs,
+                                     GtkCssParserErrorFunc   error_func,
+                                     gpointer                user_data,
+                                     GDestroyNotify          user_destroy)
+{
+  GtkCssTokenizer *tokenizer;
+  GtkCssParser *result;
+
+  tokenizer = gtk_css_tokenizer_new_for_range (value->bytes, value->offset,
+                                               value->end_offset - value->offset);
+  result = gtk_css_parser_new (tokenizer, file, error_func, user_data, user_destroy);
+  gtk_css_tokenizer_unref (tokenizer);
+
+  result->refs = refs;
+  result->n_refs = n_refs;
+  result->next_ref = 0;
+
+  return result;
+}
+
 static void
 gtk_css_parser_finalize (GtkCssParser *self)
 {
   if (self->user_destroy)
     self->user_destroy (self->user_data);
 
-  g_clear_pointer (&self->tokenizer, gtk_css_tokenizer_unref);
+  g_clear_pointer (&self->tokenizers, g_ptr_array_unref);
   g_clear_object (&self->file);
   g_clear_object (&self->directory);
   if (self->blocks->len)
     g_critical ("Finalizing CSS parser with %u remaining blocks", self->blocks->len);
   g_array_free (self->blocks, TRUE);
 
+  if (self->refs)
+    g_free (self->refs);
+
   g_free (self);
 }
 
@@ -239,7 +282,7 @@ gtk_css_parser_get_start_location (GtkCssParser *self)
 const GtkCssLocation *
 gtk_css_parser_get_end_location (GtkCssParser *self)
 {
-  return gtk_css_tokenizer_get_location (self->tokenizer);
+  return gtk_css_tokenizer_get_location (get_tokenizer (self));
 }
 
 /**
@@ -273,12 +316,14 @@ static void
 gtk_css_parser_ensure_token (GtkCssParser *self)
 {
   GError *error = NULL;
+  GtkCssTokenizer *tokenizer;
 
   if (!gtk_css_token_is (&self->token, GTK_CSS_TOKEN_EOF))
     return;
 
-  self->location = *gtk_css_tokenizer_get_location (self->tokenizer);
-  if (!gtk_css_tokenizer_read_token (self->tokenizer, &self->token, &error))
+  tokenizer = get_tokenizer (self);
+  self->location = *gtk_css_tokenizer_get_location (tokenizer);
+  if (!gtk_css_tokenizer_read_token (tokenizer, &self->token, &error))
     {
       /* We ignore the error here, because the resulting token will
        * likely already trigger an error in the parsing code and
@@ -286,6 +331,64 @@ gtk_css_parser_ensure_token (GtkCssParser *self)
        */
       g_clear_error (&error);
     }
+
+  if (self->tokenizers->len > 1 && gtk_css_token_is (&self->token, GTK_CSS_TOKEN_EOF))
+    {
+      g_ptr_array_remove_index_fast (self->tokenizers, self->tokenizers->len - 1);
+      gtk_css_parser_ensure_token (self);
+      return;
+    }
+
+  /* Resolve var(--name): skip it and insert the resolved reference instead */
+  if (self->n_refs > 0 && gtk_css_token_is_function (&self->token, "var") && self->var_fallback == 0)
+    {
+      GtkCssVariableValue *ref;
+      GtkCssTokenizer *ref_tokenizer;
+
+      gtk_css_parser_start_block (self);
+
+      if (gtk_css_parser_has_token (self, GTK_CSS_TOKEN_IDENT))
+        {
+          char *var_name = gtk_css_parser_consume_ident (self);
+
+          if (var_name[0] != '-' || var_name[1] != '-')
+            {
+              g_free (var_name);
+
+              self->var_fallback++;
+              gtk_css_parser_skip (self);
+              gtk_css_parser_end_block (self);
+              self->var_fallback--;
+              return;
+            }
+
+          g_free (var_name);
+        }
+      else
+        {
+          self->var_fallback++;
+          gtk_css_parser_skip (self);
+          gtk_css_parser_end_block (self);
+          self->var_fallback--;
+          return;
+        }
+
+      /* If we encounter var() in a fallback when we can already resolve the
+       * actual variable, skip it */
+      self->var_fallback++;
+      gtk_css_parser_skip (self);
+      gtk_css_parser_end_block (self);
+      self->var_fallback--;
+
+      g_assert (self->next_ref < self->n_refs);
+
+      ref = self->refs[self->next_ref++];
+      ref_tokenizer = gtk_css_tokenizer_new_for_range (ref->bytes, ref->offset,
+                                                       ref->end_offset - ref->offset);
+      g_ptr_array_add (self->tokenizers, ref_tokenizer);
+
+      gtk_css_parser_ensure_token (self);
+    }
 }
 
 const GtkCssToken *
@@ -1112,3 +1215,274 @@ gtk_css_parser_consume_any (GtkCssParser            *parser,
 
   return result;
 }
+
+gboolean
+gtk_css_parser_has_references (GtkCssParser *self)
+{
+  GtkCssTokenizer *tokenizer = get_tokenizer (self);
+  gboolean ret = FALSE;
+  int inner_blocks = 0, i;
+
+  gtk_css_tokenizer_save (tokenizer);
+
+  do {
+      const GtkCssToken *token;
+
+      token = gtk_css_parser_get_token (self);
+
+      if (inner_blocks == 0)
+        {
+          if (gtk_css_token_is (token, GTK_CSS_TOKEN_EOF))
+            break;
+
+          if (gtk_css_token_is (token, GTK_CSS_TOKEN_CLOSE_PARENS) ||
+              gtk_css_token_is (token, GTK_CSS_TOKEN_CLOSE_SQUARE))
+            {
+              goto error;
+            }
+        }
+
+      if (gtk_css_token_is_preserved (token, NULL))
+        {
+          if (inner_blocks > 0 && gtk_css_token_is (token, GTK_CSS_TOKEN_EOF))
+            {
+              gtk_css_parser_end_block (self);
+              inner_blocks--;
+            }
+          else
+            {
+              gtk_css_parser_consume_token (self);
+            }
+        }
+      else
+        {
+          gboolean is_var = gtk_css_token_is_function (token, "var");
+
+          inner_blocks++;
+          gtk_css_parser_start_block (self);
+
+          if (!ret && is_var)
+            {
+              token = gtk_css_parser_get_token (self);
+
+              if (gtk_css_token_is (token, GTK_CSS_TOKEN_IDENT))
+                {
+                  const char *var_name = gtk_css_token_get_string (token);
+
+                  if (var_name[0] != '-' || var_name[1] != '-')
+                    goto error;
+
+                  gtk_css_parser_consume_token (self);
+
+                  if (!gtk_css_parser_has_token (self, GTK_CSS_TOKEN_EOF) &&
+                      !gtk_css_parser_has_token (self, GTK_CSS_TOKEN_COMMA))
+                    {
+                      goto error;
+                    }
+
+                  ret = TRUE;
+                }
+            }
+        }
+    }
+  while (!gtk_css_parser_has_token (self, GTK_CSS_TOKEN_SEMICOLON) &&
+         !gtk_css_parser_has_token (self, GTK_CSS_TOKEN_CLOSE_CURLY));
+
+  if (inner_blocks > 0)
+    goto error;
+
+  gtk_css_tokenizer_restore (tokenizer);
+  self->location = *gtk_css_tokenizer_get_location (tokenizer);
+  gtk_css_tokenizer_read_token (tokenizer, &self->token, NULL);
+
+  return ret;
+
+error:
+  for (i = 0; i < inner_blocks; i++)
+    gtk_css_parser_end_block (self);
+
+  gtk_css_tokenizer_restore (tokenizer);
+  self->location = *gtk_css_tokenizer_get_location (tokenizer);
+  gtk_css_tokenizer_read_token (tokenizer, &self->token, NULL);
+
+  return FALSE;
+}
+
+static void
+clear_ref (GtkCssVariableValueReference *ref)
+{
+  g_free (ref->name);
+  if (ref->fallback)
+    gtk_css_variable_value_unref (ref->fallback);
+}
+
+GtkCssVariableValue *
+gtk_css_parser_parse_value_into_token_stream (GtkCssParser *self)
+{
+  GBytes *bytes = gtk_css_tokenizer_get_bytes (get_tokenizer (self));
+  const GtkCssToken *token;
+  gsize offset;
+  gsize length = 0;
+  GArray *refs;
+  GtkCssVariableValueReference *out_refs;
+  gsize n_refs;
+  int inner_blocks = 0, i;
+  gboolean is_initial = FALSE;
+
+  refs = g_array_new (FALSE, TRUE, sizeof (GtkCssVariableValueReference));
+
+  g_array_set_clear_func (refs, (GDestroyNotify) clear_ref);
+
+  for (token = gtk_css_parser_peek_token (self);
+       gtk_css_token_is (token, GTK_CSS_TOKEN_WHITESPACE);
+       token = gtk_css_parser_peek_token (self))
+    {
+      gtk_css_parser_consume_token (self);
+    }
+
+  offset = self->location.bytes;
+
+  do {
+      token = gtk_css_parser_get_token (self);
+
+      if (length == 0 && gtk_css_token_is_ident (token, "initial"))
+        is_initial = TRUE;
+
+      if (gtk_css_token_is (token, GTK_CSS_TOKEN_BAD_STRING) ||
+          gtk_css_token_is (token, GTK_CSS_TOKEN_BAD_URL))
+        {
+          gtk_css_parser_error_syntax (self, "Invalid property value");
+          goto error;
+        }
+
+      if (inner_blocks == 0)
+        {
+          if (gtk_css_token_is (token, GTK_CSS_TOKEN_EOF))
+            break;
+
+          if (gtk_css_token_is (token, GTK_CSS_TOKEN_CLOSE_PARENS) ||
+              gtk_css_token_is (token, GTK_CSS_TOKEN_CLOSE_SQUARE))
+            {
+              gtk_css_parser_error_syntax (self, "Invalid property value");
+              goto error;
+            }
+        }
+
+      if (gtk_css_token_is_preserved (token, NULL))
+        {
+          if (inner_blocks > 0 && gtk_css_token_is (token, GTK_CSS_TOKEN_EOF))
+            {
+              length++;
+              gtk_css_parser_end_block (self);
+
+              inner_blocks--;
+            }
+          else
+            {
+              length++;
+              gtk_css_parser_consume_token (self);
+            }
+        }
+      else
+        {
+          gboolean is_var = gtk_css_token_is_function (token, "var");
+
+          length++;
+          inner_blocks++;
+
+          gtk_css_parser_start_block (self);
+
+          if (is_var)
+            {
+              token = gtk_css_parser_get_token (self);
+
+              if (gtk_css_token_is (token, GTK_CSS_TOKEN_IDENT))
+                {
+                  GtkCssVariableValueReference ref;
+                  char *var_name = g_strdup (gtk_css_token_get_string (token));
+
+                  if (var_name[0] != '-' || var_name[1] != '-')
+                    {
+                      gtk_css_parser_error_value (self, "Invalid variable name: %s", var_name);
+                      g_free (var_name);
+                      goto error;
+                    }
+
+                  length++;
+                  gtk_css_parser_consume_token (self);
+
+                  if (!gtk_css_parser_has_token (self, GTK_CSS_TOKEN_EOF) &&
+                      !gtk_css_parser_has_token (self, GTK_CSS_TOKEN_COMMA))
+                    {
+                      gtk_css_parser_error_syntax (self, "Invalid property value");
+                      g_free (var_name);
+                      goto error;
+                    }
+
+                  ref.name = var_name;
+
+                  if (gtk_css_parser_has_token (self, GTK_CSS_TOKEN_EOF))
+                    {
+                      ref.length = 3;
+                      ref.fallback = NULL;
+                    }
+                  else
+                    {
+                      length++;
+                      gtk_css_parser_consume_token (self);
+
+                      ref.fallback = gtk_css_parser_parse_value_into_token_stream (self);
+
+                      if (ref.fallback == NULL)
+                        {
+                          gtk_css_parser_error_value (self, "Invalid fallback for: %s", var_name);
+                          g_free (var_name);
+                          goto error;
+                        }
+
+                      ref.length = 4 + ref.fallback->length;
+                      length += ref.fallback->length;
+                    }
+
+                  g_array_append_val (refs, ref);
+                }
+            }
+        }
+    }
+  while (!gtk_css_parser_has_token (self, GTK_CSS_TOKEN_SEMICOLON) &&
+         !gtk_css_parser_has_token (self, GTK_CSS_TOKEN_CLOSE_CURLY));
+
+  if (inner_blocks > 0)
+    {
+      gtk_css_parser_error_syntax (self, "Invalid property value");
+      goto error;
+    }
+
+  if (is_initial && length == 1)
+    {
+      g_array_unref (refs);
+
+      return gtk_css_variable_value_new_initial (bytes,
+                                                 offset,
+                                                 self->location.bytes);
+    }
+  else
+    {
+      out_refs = g_array_steal (refs, &n_refs);
+
+      return gtk_css_variable_value_new (bytes,
+                                         offset,
+                                         self->location.bytes,
+                                         length,
+                                         out_refs,
+                                         n_refs);
+    }
+
+error:
+  for (i = 0; i < inner_blocks; i++)
+    gtk_css_parser_end_block (self);
+
+  g_array_unref (refs);
+
+  return NULL;
+}

gtk/css/gtkcssparserprivate.h

@@ -22,6 +22,7 @@
 
 #include "gtkcssenums.h"
 #include "gtkcsstokenizerprivate.h"
+#include "gtkcssvariablevalueprivate.h"
 
 #include <gio/gio.h>
 
@@ -58,6 +59,13 @@ GtkCssParser *          gtk_css_parser_new_for_bytes            (GBytes
                                                                  GtkCssParserErrorFunc           error_func,
                                                                  gpointer                        user_data,
                                                                  GDestroyNotify                  user_destroy);
+GtkCssParser *          gtk_css_parser_new_for_token_stream     (GtkCssVariableValue            *value,
+                                                                 GFile                          *file,
+                                                                 GtkCssVariableValue           **refs,
+                                                                 gsize                           n_refs,
+                                                                 GtkCssParserErrorFunc           error_func,
+                                                                 gpointer                        user_data,
+                                                                 GDestroyNotify                  user_destroy);
 GtkCssParser *          gtk_css_parser_ref                      (GtkCssParser                   *self);
 void                    gtk_css_parser_unref                    (GtkCssParser                   *self);
 
@@ -150,5 +158,9 @@ gsize                   gtk_css_parser_consume_any              (GtkCssParser
                                                                  gsize                           n_options,
                                                                  gpointer                        user_data);
 
+gboolean                gtk_css_parser_has_references           (GtkCssParser                   *parser);
+
+GtkCssVariableValue *   gtk_css_parser_parse_value_into_token_stream (GtkCssParser              *parser);
+
 G_END_DECLS
 

gtk/css/gtkcsstokenizer.c

@@ -36,8 +36,15 @@ struct _GtkCssTokenizer
   const char            *end;
 
   GtkCssLocation         position;
+  GArray                *saved_states;
 };
 
+typedef struct
+{
+  GtkCssLocation         position;
+  const char            *data;
+} GtkCssTokenizerSavedState;
+
 void
 gtk_css_token_clear (GtkCssToken *token)
 {
@@ -568,6 +575,14 @@ gtk_css_token_init_dimension (GtkCssToken     *token,
 
 GtkCssTokenizer *
 gtk_css_tokenizer_new (GBytes *bytes)
+{
+  return gtk_css_tokenizer_new_for_range (bytes, 0, g_bytes_get_size (bytes));
+}
+
+GtkCssTokenizer *
+gtk_css_tokenizer_new_for_range (GBytes *bytes,
+                                 gsize   offset,
+                                 gsize   length)
 {
   GtkCssTokenizer *tokenizer;
 
@@ -576,10 +591,11 @@ gtk_css_tokenizer_new (GBytes *bytes)
   tokenizer->bytes = g_bytes_ref (bytes);
   tokenizer->name_buffer = g_string_new (NULL);
 
-  tokenizer->data = g_bytes_get_data (bytes, NULL);
-  tokenizer->end = tokenizer->data + g_bytes_get_size (bytes);
+  tokenizer->data = g_bytes_get_region (bytes, 1, offset, length);
+  tokenizer->end = tokenizer->data + length;
 
   gtk_css_location_init (&tokenizer->position);
+  tokenizer->saved_states = g_array_new (FALSE, FALSE, sizeof (GtkCssTokenizerSavedState));
 
   return tokenizer;
 }
@@ -601,9 +617,16 @@ gtk_css_tokenizer_unref (GtkCssTokenizer *tokenizer)
 
   g_string_free (tokenizer->name_buffer, TRUE);
   g_bytes_unref (tokenizer->bytes);
+  g_array_unref (tokenizer->saved_states);
   g_free (tokenizer);
 }
 
+GBytes *
+gtk_css_tokenizer_get_bytes (GtkCssTokenizer *tokenizer)
+{
+  return tokenizer->bytes;
+}
+
 const GtkCssLocation *
 gtk_css_tokenizer_get_location (GtkCssTokenizer *tokenizer)
 {
@@ -1020,7 +1043,7 @@ gtk_css_tokenizer_read_ident_like (GtkCssTokenizer  *tokenizer,
 {
   gtk_css_tokenizer_read_name (tokenizer);
 
-  if (*tokenizer->data == '(')
+  if (gtk_css_tokenizer_remaining (tokenizer) > 0 && *tokenizer->data == '(')
     {
       gtk_css_tokenizer_consume_ascii (tokenizer);
       if (g_ascii_strcasecmp (tokenizer->name_buffer->str, "url") == 0)
@@ -1484,3 +1507,29 @@ gtk_css_tokenizer_read_token (GtkCssTokenizer  *tokenizer,
     }
 }
 
+void
+gtk_css_tokenizer_save (GtkCssTokenizer *tokenizer)
+{
+  GtkCssTokenizerSavedState state;
+
+  state.position = tokenizer->position;
+  state.data = tokenizer->data;
+
+  g_array_append_val (tokenizer->saved_states, state);
+}
+
+void
+gtk_css_tokenizer_restore (GtkCssTokenizer *tokenizer)
+{
+  GtkCssTokenizerSavedState state;
+
+  int index = tokenizer->saved_states->len - 1;
+
+  g_assert (index >= 0);
+
+  state = g_array_index (tokenizer->saved_states, GtkCssTokenizerSavedState, index);
+  g_array_remove_index_fast (tokenizer->saved_states, index);
+
+  tokenizer->position = state.position;
+  tokenizer->data = state.data;
+}

gtk/css/gtkcsstokenizerprivate.h

@@ -138,15 +138,22 @@ void                    gtk_css_token_print                     (const GtkCssTok
 char *                  gtk_css_token_to_string                 (const GtkCssToken      *token);
 
 GtkCssTokenizer *       gtk_css_tokenizer_new                   (GBytes                 *bytes);
+GtkCssTokenizer *       gtk_css_tokenizer_new_for_range         (GBytes                 *bytes,
+                                                                 gsize                   offset,
+                                                                 gsize                   length);
 
 GtkCssTokenizer *       gtk_css_tokenizer_ref                   (GtkCssTokenizer        *tokenizer);
 void                    gtk_css_tokenizer_unref                 (GtkCssTokenizer        *tokenizer);
 
+GBytes *                gtk_css_tokenizer_get_bytes             (GtkCssTokenizer        *tokenizer);
 const GtkCssLocation *  gtk_css_tokenizer_get_location          (GtkCssTokenizer        *tokenizer) G_GNUC_CONST;
 
 gboolean                gtk_css_tokenizer_read_token            (GtkCssTokenizer        *tokenizer,
                                                                  GtkCssToken            *token,
                                                                  GError                **error);
 
+void                     gtk_css_tokenizer_save                 (GtkCssTokenizer        *tokenizer);
+void                     gtk_css_tokenizer_restore              (GtkCssTokenizer        *tokenizer);
+
 G_END_DECLS
 

gtk/css/gtkcssvariablevalue.c

@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2023 GNOME Foundation Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Alice Mikhaylenko <alicem@gnome.org>
+ */
+
+#include "gtkcssvariablevalueprivate.h"
+
+GtkCssVariableValue *
+gtk_css_variable_value_new (GBytes                       *bytes,
+                            gsize                         offset,
+                            gsize                         end_offset,
+                            gsize                         length,
+                            GtkCssVariableValueReference *references,
+                            gsize                         n_references)
+{
+  GtkCssVariableValue *self = g_new0 (GtkCssVariableValue, 1);
+
+  self->ref_count = 1;
+
+  self->bytes = g_bytes_ref (bytes);
+  self->offset = offset;
+  self->end_offset = end_offset;
+  self->length = length;
+
+  self->references = references;
+  self->n_references = n_references;
+
+  return self;
+}
+
+GtkCssVariableValue *
+gtk_css_variable_value_new_initial (GBytes *bytes,
+                                    gsize   offset,
+                                    gsize   end_offset)
+{
+  GtkCssVariableValue *self = gtk_css_variable_value_new (bytes, offset, end_offset, 1, NULL, 0);
+
+  self->is_invalid = TRUE;
+
+  return self;
+}
+
+GtkCssVariableValue *
+gtk_css_variable_value_ref (GtkCssVariableValue *self)
+{
+  self->ref_count++;
+
+  return self;
+}
+
+void
+gtk_css_variable_value_unref (GtkCssVariableValue *self)
+{
+  gsize i;
+
+  self->ref_count--;
+  if (self->ref_count > 0)
+    return;
+
+  g_bytes_unref (self->bytes);
+
+  for (i = 0; i < self->n_references; i++)
+    {
+      GtkCssVariableValueReference *ref = &self->references[i];
+
+      g_free (ref->name);
+      if (ref->fallback)
+        gtk_css_variable_value_unref (ref->fallback);
+    }
+
+  g_free (self->references);
+  g_free (self);
+}
+
+void
+gtk_css_variable_value_print (GtkCssVariableValue *self,
+                              GString             *string)
+{
+  gsize len = self->end_offset - self->offset;
+  gconstpointer data = g_bytes_get_region (self->bytes, 1, self->offset, len);
+
+  g_assert (data != NULL);
+
+  g_string_append_len (string, (const char *) data, len);
+}
+
+gboolean
+gtk_css_variable_value_equal (const GtkCssVariableValue *value1,
+                              const GtkCssVariableValue *value2)
+{
+  if (value1 == value2)
+    return TRUE;
+
+  if (value1 == NULL || value2 == NULL)
+    return FALSE;
+
+  if (value1->bytes != value2->bytes)
+    return FALSE;
+
+  if (value1->offset != value2->offset)
+    return FALSE;
+
+  if (value1->end_offset != value2->end_offset)
+    return FALSE;
+
+  return TRUE;
+}
+
+GtkCssVariableValue *
+gtk_css_variable_value_transition  (GtkCssVariableValue *start,
+                                    GtkCssVariableValue *end,
+                                    double               progress)
+{
+  GtkCssVariableValue *ret = progress < 0.5 ? start : end;
+
+  if (ret == NULL)
+    return NULL;
+
+  return gtk_css_variable_value_ref (ret);
+}
+
+void
+gtk_css_variable_value_set_section (GtkCssVariableValue *self,
+                                    GtkCssSection       *section)
+{
+  self->section = gtk_css_section_ref (section);
+}

gtk/css/gtkcssvariablevalueprivate.h

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2023 GNOME Foundation Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Alice Mikhaylenko <alicem@gnome.org>
+ */
+
+#pragma once
+
+#include "gtkcss.h"
+#include "gtkcsstokenizerprivate.h"
+
+G_BEGIN_DECLS
+
+typedef struct _GtkCssVariableValueReference GtkCssVariableValueReference;
+typedef struct _GtkCssVariableValue GtkCssVariableValue;
+
+struct _GtkCssVariableValueReference
+{
+  char *name;
+  gsize length;
+  GtkCssVariableValue *fallback;
+};
+
+struct _GtkCssVariableValue
+{
+  int ref_count;
+
+  GBytes *bytes;
+  gsize offset;
+  gsize end_offset;
+  gsize length;
+
+  GtkCssVariableValueReference *references;
+  gsize n_references;
+
+  GtkCssSection *section;
+  gboolean is_invalid;
+};
+
+GtkCssVariableValue *gtk_css_variable_value_new         (GBytes                       *bytes,
+                                                         gsize                         offset,
+                                                         gsize                         end_offset,
+                                                         gsize                         length,
+                                                         GtkCssVariableValueReference *references,
+                                                         gsize                         n_references);
+GtkCssVariableValue *gtk_css_variable_value_new_initial (GBytes                       *bytes,
+                                                         gsize                         offset,
+                                                         gsize                         end_offset);
+GtkCssVariableValue *gtk_css_variable_value_ref         (GtkCssVariableValue          *self);
+void                 gtk_css_variable_value_unref       (GtkCssVariableValue          *self);
+void                 gtk_css_variable_value_print       (GtkCssVariableValue          *self,
+                                                         GString                      *string);
+gboolean             gtk_css_variable_value_equal       (const GtkCssVariableValue    *value1,
+                                                         const GtkCssVariableValue    *value2) G_GNUC_PURE;
+GtkCssVariableValue *gtk_css_variable_value_transition  (GtkCssVariableValue          *start,
+                                                         GtkCssVariableValue          *end,
+                                                         double                        progress);
+void                 gtk_css_variable_value_set_section (GtkCssVariableValue          *self,
+                                                         GtkCssSection                *section);
+
+G_END_DECLS

gtk/css/meson.build

@@ -6,8 +6,9 @@ gtk_css_public_sources = files([
 gtk_css_private_sources = files([
   'gtkcssdataurl.c',
   'gtkcssparser.c',
-  'gtkcsstokenizer.c',
   'gtkcssserializer.c',
+  'gtkcsstokenizer.c',
+  'gtkcssvariablevalue.c',
 ])
 
 gtk_css_public_headers = files([

gtk/gtkapplication-quartz.c

@@ -48,7 +48,6 @@ typedef struct
 
   GtkActionMuxer *muxer;
   GMenu *combined;
-  GMenuModel *standard_app_menu;
 
   GSList *inhibitors;
   int quit_inhibit;
@@ -151,29 +150,6 @@ static GActionEntry gtk_application_impl_quartz_actions[] = {
   { "show-all",         gtk_application_impl_quartz_show_all    }
 };
 
-static void
-gtk_application_impl_quartz_set_app_menu (GtkApplicationImpl *impl,
-                                          GMenuModel         *app_menu)
-{
-  GtkApplicationImplQuartz *quartz = (GtkApplicationImplQuartz *) impl;
-
-  /* If there are any items at all, then the first one is the app menu */
-  if (g_menu_model_get_n_items (G_MENU_MODEL (quartz->combined)))
-    g_menu_remove (quartz->combined, 0);
-
-  if (app_menu)
-    g_menu_prepend_submenu (quartz->combined, "Application", app_menu);
-  else
-    {
-      GMenu *empty;
-
-      /* We must preserve the rule that index 0 is the app menu */
-      empty = g_menu_new ();
-      g_menu_prepend_submenu (quartz->combined, "Application", G_MENU_MODEL (empty));
-      g_object_unref (empty);
-    }
-}
-
 static void
 gtk_application_impl_quartz_startup (GtkApplicationImpl *impl,
                                      gboolean            register_session)
@@ -208,23 +184,6 @@ gtk_application_impl_quartz_startup (GtkApplicationImpl *impl,
   g_object_unref (gtkinternal);
 
   /* now setup the menu */
-  if (quartz->standard_app_menu == NULL)
-    {
-      GtkBuilder *builder;
-
-      /* If the user didn't fill in their own menu yet, add ours.
-       *
-       * The fact that we do this here ensures that we will always have the
-       * app menu at index 0 in 'combined'.
-       */
-      builder = gtk_builder_new_from_resource ("/org/gtk/libgtk/ui/gtkapplication-quartz.ui");
-      quartz->standard_app_menu = G_MENU_MODEL (g_object_ref (gtk_builder_get_object (builder, "app-menu")));
-      g_object_unref (builder);
-    }
-
-  gtk_application_impl_quartz_set_app_menu (impl, quartz->standard_app_menu);
-
-  /* This may or may not add an item to 'combined' */
   gtk_application_impl_set_menubar (impl, gtk_application_get_menubar (impl->application));
 
   /* OK.  Now put it in the menu. */
@@ -295,12 +254,30 @@ gtk_application_impl_quartz_set_menubar (GtkApplicationImpl *impl,
 {
   GtkApplicationImplQuartz *quartz = (GtkApplicationImplQuartz *) impl;
 
-  /* If we have the menubar, it is a section at index '1' */
-  if (g_menu_model_get_n_items (G_MENU_MODEL (quartz->combined)) > 1)
-    g_menu_remove (quartz->combined, 1);
+  /* If we have the menubar, it is a section at index '0' */
+  if (g_menu_model_get_n_items (G_MENU_MODEL (quartz->combined)))
+    g_menu_remove (quartz->combined, 0);
 
   if (menubar)
     g_menu_append_section (quartz->combined, NULL, menubar);
+  else
+    {
+      // Ensure that we will always have one menu.
+      char app_menu_key[] = "APP_MENU";
+      GMenuModel *app_menu = g_object_get_data (G_OBJECT (impl), app_menu_key);
+      if (app_menu == NULL)
+        {
+          GtkBuilder *builder;
+
+          // If the user didn't fill in their own menu yet, add ours.
+          builder = gtk_builder_new_from_resource ("/org/gtk/libgtk/ui/gtkapplication-quartz.ui");
+          app_menu = G_MENU_MODEL (gtk_builder_get_object (builder, "app-menu"));
+          g_object_set_data_full (G_OBJECT (impl), app_menu_key, g_object_ref (app_menu), g_object_unref);
+          g_object_unref (builder);
+        }
+
+      g_menu_append_submenu (quartz->combined, "Application", app_menu);
+    }
 }
 
 static guint
@@ -369,7 +346,6 @@ gtk_application_impl_quartz_finalize (GObject *object)
   GtkApplicationImplQuartz *quartz = (GtkApplicationImplQuartz *) object;
 
   g_clear_object (&quartz->combined);
-  g_clear_object (&quartz->standard_app_menu);
 
   G_OBJECT_CLASS (gtk_application_impl_quartz_parent_class)->finalize (object);
 }
@@ -382,7 +358,6 @@ gtk_application_impl_quartz_class_init (GtkApplicationImplClass *class)
   class->startup = gtk_application_impl_quartz_startup;
   class->shutdown = gtk_application_impl_quartz_shutdown;
   class->active_window_changed = gtk_application_impl_quartz_active_window_changed;
-  class->set_app_menu = gtk_application_impl_quartz_set_app_menu;
   class->set_menubar = gtk_application_impl_quartz_set_menubar;
   class->inhibit = gtk_application_impl_quartz_inhibit;
   class->uninhibit = gtk_application_impl_quartz_uninhibit;

gtk/gtkcssanimatedstyle.c

@@ -37,9 +37,178 @@
 #include "gtkstyleanimationprivate.h"
 #include "gtkstylepropertyprivate.h"
 #include "gtkstyleproviderprivate.h"
+#include "gtkcsscustompropertypoolprivate.h"
 
 G_DEFINE_TYPE (GtkCssAnimatedStyle, gtk_css_animated_style, GTK_TYPE_CSS_STYLE)
 
+static const int core_props[] = {
+  GTK_CSS_PROPERTY_COLOR,
+  GTK_CSS_PROPERTY_DPI,
+  GTK_CSS_PROPERTY_FONT_SIZE,
+  GTK_CSS_PROPERTY_ICON_PALETTE
+};
+
+static const int background_props[] = {
+  GTK_CSS_PROPERTY_BACKGROUND_COLOR,
+  GTK_CSS_PROPERTY_BOX_SHADOW,
+  GTK_CSS_PROPERTY_BACKGROUND_CLIP,
+  GTK_CSS_PROPERTY_BACKGROUND_ORIGIN,
+  GTK_CSS_PROPERTY_BACKGROUND_SIZE,
+  GTK_CSS_PROPERTY_BACKGROUND_POSITION,
+  GTK_CSS_PROPERTY_BACKGROUND_REPEAT,
+  GTK_CSS_PROPERTY_BACKGROUND_IMAGE,
+  GTK_CSS_PROPERTY_BACKGROUND_BLEND_MODE
+};
+
+static const int border_props[] = {
+  GTK_CSS_PROPERTY_BORDER_TOP_STYLE,
+  GTK_CSS_PROPERTY_BORDER_TOP_WIDTH,
+  GTK_CSS_PROPERTY_BORDER_LEFT_STYLE,
+  GTK_CSS_PROPERTY_BORDER_LEFT_WIDTH,
+  GTK_CSS_PROPERTY_BORDER_BOTTOM_STYLE,
+  GTK_CSS_PROPERTY_BORDER_BOTTOM_WIDTH,
+  GTK_CSS_PROPERTY_BORDER_RIGHT_STYLE,
+  GTK_CSS_PROPERTY_BORDER_RIGHT_WIDTH,
+  GTK_CSS_PROPERTY_BORDER_TOP_LEFT_RADIUS,
+  GTK_CSS_PROPERTY_BORDER_TOP_RIGHT_RADIUS,
+  GTK_CSS_PROPERTY_BORDER_BOTTOM_RIGHT_RADIUS,
+  GTK_CSS_PROPERTY_BORDER_BOTTOM_LEFT_RADIUS,
+  GTK_CSS_PROPERTY_BORDER_TOP_COLOR,
+  GTK_CSS_PROPERTY_BORDER_RIGHT_COLOR,
+  GTK_CSS_PROPERTY_BORDER_BOTTOM_COLOR,
+  GTK_CSS_PROPERTY_BORDER_LEFT_COLOR,
+  GTK_CSS_PROPERTY_BORDER_IMAGE_SOURCE,
+  GTK_CSS_PROPERTY_BORDER_IMAGE_REPEAT,
+  GTK_CSS_PROPERTY_BORDER_IMAGE_SLICE,
+  GTK_CSS_PROPERTY_BORDER_IMAGE_WIDTH
+};
+
+static const int icon_props[] = {
+  GTK_CSS_PROPERTY_ICON_SIZE,
+  GTK_CSS_PROPERTY_ICON_SHADOW,
+  GTK_CSS_PROPERTY_ICON_STYLE,
+};
+
+static const int outline_props[] = {
+  GTK_CSS_PROPERTY_OUTLINE_STYLE,
+  GTK_CSS_PROPERTY_OUTLINE_WIDTH,
+  GTK_CSS_PROPERTY_OUTLINE_OFFSET,
+  GTK_CSS_PROPERTY_OUTLINE_COLOR,
+};
+
+static const int font_props[] = {
+  GTK_CSS_PROPERTY_FONT_FAMILY,
+  GTK_CSS_PROPERTY_FONT_STYLE,
+  GTK_CSS_PROPERTY_FONT_WEIGHT,
+  GTK_CSS_PROPERTY_FONT_STRETCH,
+  GTK_CSS_PROPERTY_LETTER_SPACING,
+  GTK_CSS_PROPERTY_TEXT_SHADOW,
+  GTK_CSS_PROPERTY_CARET_COLOR,
+  GTK_CSS_PROPERTY_SECONDARY_CARET_COLOR,
+  GTK_CSS_PROPERTY_FONT_FEATURE_SETTINGS,
+  GTK_CSS_PROPERTY_FONT_VARIATION_SETTINGS,
+  GTK_CSS_PROPERTY_LINE_HEIGHT,
+};
+static const int font_variant_props[] = {
+  GTK_CSS_PROPERTY_TEXT_DECORATION_LINE,
+  GTK_CSS_PROPERTY_TEXT_DECORATION_COLOR,
+  GTK_CSS_PROPERTY_TEXT_DECORATION_STYLE,
+  GTK_CSS_PROPERTY_TEXT_TRANSFORM,
+  GTK_CSS_PROPERTY_FONT_KERNING,
+  GTK_CSS_PROPERTY_FONT_VARIANT_LIGATURES,
+  GTK_CSS_PROPERTY_FONT_VARIANT_POSITION,
+  GTK_CSS_PROPERTY_FONT_VARIANT_CAPS,
+  GTK_CSS_PROPERTY_FONT_VARIANT_NUMERIC,
+  GTK_CSS_PROPERTY_FONT_VARIANT_ALTERNATES,
+  GTK_CSS_PROPERTY_FONT_VARIANT_EAST_ASIAN,
+};
+
+static const int animation_props[] = {
+  GTK_CSS_PROPERTY_ANIMATION_NAME,
+  GTK_CSS_PROPERTY_ANIMATION_DURATION,
+  GTK_CSS_PROPERTY_ANIMATION_TIMING_FUNCTION,
+  GTK_CSS_PROPERTY_ANIMATION_ITERATION_COUNT,
+  GTK_CSS_PROPERTY_ANIMATION_DIRECTION,
+  GTK_CSS_PROPERTY_ANIMATION_PLAY_STATE,
+  GTK_CSS_PROPERTY_ANIMATION_DELAY,
+  GTK_CSS_PROPERTY_ANIMATION_FILL_MODE,
+};
+
+static const int transition_props[] = {
+  GTK_CSS_PROPERTY_TRANSITION_PROPERTY,
+  GTK_CSS_PROPERTY_TRANSITION_DURATION,
+  GTK_CSS_PROPERTY_TRANSITION_TIMING_FUNCTION,
+  GTK_CSS_PROPERTY_TRANSITION_DELAY,
+};
+
+static const int size_props[] = {
+  GTK_CSS_PROPERTY_MARGIN_TOP,
+  GTK_CSS_PROPERTY_MARGIN_LEFT,
+  GTK_CSS_PROPERTY_MARGIN_BOTTOM,
+  GTK_CSS_PROPERTY_MARGIN_RIGHT,
+  GTK_CSS_PROPERTY_PADDING_TOP,
+  GTK_CSS_PROPERTY_PADDING_LEFT,
+  GTK_CSS_PROPERTY_PADDING_BOTTOM,
+  GTK_CSS_PROPERTY_PADDING_RIGHT,
+  GTK_CSS_PROPERTY_BORDER_SPACING,
+  GTK_CSS_PROPERTY_MIN_WIDTH,
+  GTK_CSS_PROPERTY_MIN_HEIGHT,
+};
+
+static const int other_props[] = {
+  GTK_CSS_PROPERTY_ICON_SOURCE,
+  GTK_CSS_PROPERTY_ICON_TRANSFORM,
+  GTK_CSS_PROPERTY_ICON_FILTER,
+  GTK_CSS_PROPERTY_TRANSFORM,
+  GTK_CSS_PROPERTY_TRANSFORM_ORIGIN,
+  GTK_CSS_PROPERTY_OPACITY,
+  GTK_CSS_PROPERTY_FILTER,
+};
+
+#define DEFINE_VALUES(ENUM, TYPE, NAME) \
+static inline void \
+gtk_css_ ## NAME ## _values_recompute (GtkCssAnimatedStyle *animated) \
+{ \
+  GtkCssStyle *style = (GtkCssStyle *)animated; \
+  GtkCssValue **values = (GtkCssValue **)((guint8*)(animated->style->NAME) + sizeof (GtkCssValues)); \
+  int i; \
+\
+  for (i = 0; i < G_N_ELEMENTS (NAME ## _props); i++) \
+    { \
+      guint id = NAME ## _props[i]; \
+      GtkCssValue *original, *computed; \
+\
+      if (values[i] == NULL) \
+        continue; \
+\
+      original = gtk_css_style_get_original_value (style, id); \
+      if (original == NULL) \
+        continue; \
+\
+      computed = _gtk_css_value_compute (original, \
+                                         id, \
+                                         animated->provider, \
+                                         style, \
+                                         animated->parent_style, \
+                                         NULL); \
+      if (computed == NULL) \
+        continue; \
+\
+      gtk_css_animated_style_set_animated_value (animated, id, computed); \
+    } \
+}
+
+DEFINE_VALUES (CORE, Core, core)
+DEFINE_VALUES (BACKGROUND, Background, background)
+DEFINE_VALUES (BORDER, Border, border)
+DEFINE_VALUES (ICON, Icon, icon)
+DEFINE_VALUES (OUTLINE, Outline, outline)
+DEFINE_VALUES (FONT, Font, font)
+DEFINE_VALUES (FONT_VARIANT, FontVariant, font_variant)
+DEFINE_VALUES (ANIMATION, Animation, animation)
+DEFINE_VALUES (TRANSITION, Transition, transition)
+DEFINE_VALUES (SIZE, Size, size)
+DEFINE_VALUES (OTHER, Other, other)
 
 static GtkCssSection *
 gtk_css_animated_style_get_section (GtkCssStyle *style,
@@ -74,6 +243,15 @@ gtk_css_animated_style_get_static_style (GtkCssStyle *style)
   return (GtkCssStaticStyle *)animated->style;
 }
 
+static GtkCssValue *
+gtk_css_animated_style_get_original_value (GtkCssStyle *style,
+                                           guint        id)
+{
+  GtkCssAnimatedStyle *animated = GTK_CSS_ANIMATED_STYLE (style);
+
+  return gtk_css_style_get_original_value (animated->style, id);
+}
+
 static void
 gtk_css_animated_style_dispose (GObject *object)
 {
@@ -96,6 +274,9 @@ gtk_css_animated_style_finalize (GObject *object)
   GtkCssAnimatedStyle *style = GTK_CSS_ANIMATED_STYLE (object);
 
   g_object_unref (style->style);
+  if (style->parent_style)
+    g_object_unref (style->parent_style);
+  g_object_unref (style->provider);
 
   G_OBJECT_CLASS (gtk_css_animated_style_parent_class)->finalize (object);
 }
@@ -112,6 +293,7 @@ gtk_css_animated_style_class_init (GtkCssAnimatedStyleClass *klass)
   style_class->get_section = gtk_css_animated_style_get_section;
   style_class->is_static = gtk_css_animated_style_is_static;
   style_class->get_static_style = gtk_css_animated_style_get_static_style;
+  style_class->get_original_value = gtk_css_animated_style_get_original_value;
 }
 
 static void
@@ -546,6 +728,51 @@ gtk_css_animated_style_get_intrinsic_value (GtkCssAnimatedStyle *style,
   return gtk_css_style_get_value (style->style, id);
 }
 
+void
+gtk_css_animated_style_set_animated_custom_value (GtkCssAnimatedStyle *animated,
+                                                  int                  id,
+                                                  GtkCssVariableValue *value)
+{
+  GtkCssStyle *style = (GtkCssStyle *)animated;
+
+  gtk_internal_return_if_fail (GTK_IS_CSS_ANIMATED_STYLE (style));
+  gtk_internal_return_if_fail (value != NULL);
+
+  if (style->variables == NULL)
+    {
+      style->variables = gtk_css_variable_set_new ();
+      if (animated->parent_style)
+        gtk_css_variable_set_set_parent (style->variables,
+                                         animated->parent_style->variables);
+    }
+  else if (style->variables == animated->style->variables)
+    {
+      gtk_css_variable_set_unref (style->variables);
+      style->variables = gtk_css_variable_set_copy (animated->style->variables);
+    }
+
+  gtk_css_variable_set_add (style->variables, id, value);
+
+  gtk_css_core_values_recompute (animated);
+  gtk_css_background_values_recompute (animated);
+  gtk_css_border_values_recompute (animated);
+  gtk_css_icon_values_recompute (animated);
+  gtk_css_outline_values_recompute (animated);
+  gtk_css_font_values_recompute (animated);
+  gtk_css_font_variant_values_recompute (animated);
+  gtk_css_animation_values_recompute (animated);
+  gtk_css_transition_values_recompute (animated);
+  gtk_css_size_values_recompute (animated);
+  gtk_css_other_values_recompute (animated);
+}
+
+GtkCssVariableValue *
+gtk_css_animated_style_get_intrinsic_custom_value (GtkCssAnimatedStyle *style,
+                                                   int                  id)
+{
+  return gtk_css_style_get_custom_property (style->style, id);
+}
+
 static GPtrArray *
 gtk_css_animated_style_create_dynamic (GPtrArray   *animations,
                                        GtkCssStyle *style,
@@ -770,7 +997,6 @@ gtk_css_animated_style_find_animation (GtkStyleAnimation **animations,
 static GPtrArray *
 gtk_css_animated_style_create_css_animations (GPtrArray        *animations,
                                               GtkCssStyle      *base_style,
-                                              GtkCssStyle      *parent_style,
                                               gint64            timestamp,
                                               GtkStyleProvider *provider,
                                               GtkCssStyle      *source)
@@ -832,8 +1058,6 @@ gtk_css_animated_style_create_css_animations (GPtrArray        *animations,
           if (keyframes == NULL)
             continue;
 
-          keyframes = _gtk_css_keyframes_compute (keyframes, provider, base_style, parent_style);
-
           animation = _gtk_css_animation_new (name,
                                               keyframes,
                                               timestamp,
@@ -844,7 +1068,6 @@ gtk_css_animated_style_create_css_animations (GPtrArray        *animations,
                                               _gtk_css_play_state_value_get (_gtk_css_array_value_get_nth (play_states, i)),
                                               _gtk_css_fill_mode_value_get (_gtk_css_array_value_get_nth (fill_modes, i)),
                                               _gtk_css_number_value_get (_gtk_css_array_value_get_nth (iteration_counts, i), 100));
-          _gtk_css_keyframes_unref (keyframes);
         }
 
       if (!animations)
@@ -893,7 +1116,7 @@ gtk_css_animated_style_new (GtkCssStyle      *base_style,
   if (previous_style != NULL)
     animations = gtk_css_animated_style_create_css_transitions (animations, base_style, timestamp, previous_style);
 
-  animations = gtk_css_animated_style_create_css_animations (animations, base_style, parent_style, timestamp, provider, previous_style);
+  animations = gtk_css_animated_style_create_css_animations (animations, base_style, timestamp, provider, previous_style);
   animations = gtk_css_animated_style_create_dynamic (animations, base_style, timestamp);
 
   if (animations == NULL)
@@ -902,6 +1125,9 @@ gtk_css_animated_style_new (GtkCssStyle      *base_style,
   result = g_object_new (GTK_TYPE_CSS_ANIMATED_STYLE, NULL);
 
   result->style = g_object_ref (base_style);
+  if (parent_style)
+    result->parent_style = g_object_ref (parent_style);
+  result->provider = g_object_ref (provider);
   result->current_time = timestamp;
   result->n_animations = animations->len;
   result->animations = g_ptr_array_free (animations, FALSE);
@@ -918,6 +1144,8 @@ gtk_css_animated_style_new (GtkCssStyle      *base_style,
   style->transition = (GtkCssTransitionValues *)gtk_css_values_ref ((GtkCssValues *)base_style->transition);
   style->size = (GtkCssSizeValues *)gtk_css_values_ref ((GtkCssValues *)base_style->size);
   style->other = (GtkCssOtherValues *)gtk_css_values_ref ((GtkCssValues *)base_style->other);
+  if (base_style->variables)
+    style->variables = gtk_css_variable_set_ref (base_style->variables);
 
   gtk_css_animated_style_apply_animations (result);
 
@@ -927,7 +1155,9 @@ gtk_css_animated_style_new (GtkCssStyle      *base_style,
 GtkCssStyle *
 gtk_css_animated_style_new_advance (GtkCssAnimatedStyle *source,
                                     GtkCssStyle         *base_style,
-                                    gint64               timestamp)
+                                    GtkCssStyle         *parent_style,
+                                    gint64               timestamp,
+                                    GtkStyleProvider    *provider)
 {
   GtkCssAnimatedStyle *result;
   GtkCssStyle *style;
@@ -936,6 +1166,8 @@ gtk_css_animated_style_new_advance (GtkCssAnimatedStyle *source,
 
   gtk_internal_return_val_if_fail (GTK_IS_CSS_ANIMATED_STYLE (source), NULL);
   gtk_internal_return_val_if_fail (GTK_IS_CSS_STYLE (base_style), NULL);
+  gtk_internal_return_val_if_fail (parent_style == NULL || GTK_IS_CSS_STYLE (parent_style), NULL);
+  gtk_internal_return_val_if_fail (GTK_IS_STYLE_PROVIDER (provider), NULL);
 
   if (timestamp == 0)
     return g_object_ref (source->style);
@@ -966,6 +1198,9 @@ gtk_css_animated_style_new_advance (GtkCssAnimatedStyle *source,
   result = g_object_new (GTK_TYPE_CSS_ANIMATED_STYLE, NULL);
 
   result->style = g_object_ref (base_style);
+  if (parent_style)
+    result->parent_style = g_object_ref (parent_style);
+  result->provider = g_object_ref (provider);
   result->current_time = timestamp;
   result->n_animations = animations->len;
   result->animations = g_ptr_array_free (animations, FALSE);
@@ -982,8 +1217,34 @@ gtk_css_animated_style_new_advance (GtkCssAnimatedStyle *source,
   style->transition = (GtkCssTransitionValues *)gtk_css_values_ref ((GtkCssValues *)base_style->transition);
   style->size = (GtkCssSizeValues *)gtk_css_values_ref ((GtkCssValues *)base_style->size);
   style->other = (GtkCssOtherValues *)gtk_css_values_ref ((GtkCssValues *)base_style->other);
+  if (base_style->variables)
+    style->variables = gtk_css_variable_set_ref (base_style->variables);
 
   gtk_css_animated_style_apply_animations (result);
 
   return GTK_CSS_STYLE (result);
 }
+
+GtkCssStyle *
+gtk_css_animated_style_get_base_style (GtkCssAnimatedStyle *style)
+{
+  gtk_internal_return_val_if_fail (GTK_IS_CSS_ANIMATED_STYLE (style), NULL);
+
+  return style->style;
+}
+
+GtkCssStyle *
+gtk_css_animated_style_get_parent_style (GtkCssAnimatedStyle *style)
+{
+  gtk_internal_return_val_if_fail (GTK_IS_CSS_ANIMATED_STYLE (style), NULL);
+
+  return style->parent_style;
+}
+
+GtkStyleProvider *
+gtk_css_animated_style_get_provider (GtkCssAnimatedStyle *style)
+{
+  gtk_internal_return_val_if_fail (GTK_IS_CSS_ANIMATED_STYLE (style), NULL);
+
+  return style->provider;
+}

gtk/gtkcssanimatedstyleprivate.h

@@ -38,6 +38,8 @@ struct _GtkCssAnimatedStyle
   GtkCssStyle parent;
 
   GtkCssStyle           *style;                /* the style if we weren't animating */
+  GtkCssStyle           *parent_style;
+  GtkStyleProvider      *provider;
 
   gint64                 current_time;         /* the current time in our world */
   gpointer              *animations;           /* GtkStyleAnimation**, least important one first */
@@ -57,15 +59,26 @@ GtkCssStyle *           gtk_css_animated_style_new              (GtkCssStyle
                                                                  GtkStyleProvider       *provider,
                                                                  GtkCssStyle            *previous_style);
 GtkCssStyle *           gtk_css_animated_style_new_advance      (GtkCssAnimatedStyle    *source,
-                                                                 GtkCssStyle            *base,
-                                                                 gint64                  timestamp);
+                                                                 GtkCssStyle            *base_style,
+                                                                 GtkCssStyle            *parent_style,
+                                                                 gint64                  timestamp,
+                                                                 GtkStyleProvider       *provider);
 
 void                    gtk_css_animated_style_set_animated_value(GtkCssAnimatedStyle   *style,
                                                                  guint                   id,
                                                                  GtkCssValue            *value);
-
 GtkCssValue *           gtk_css_animated_style_get_intrinsic_value (GtkCssAnimatedStyle *style,
                                                                  guint                   id);
 
+void                    gtk_css_animated_style_set_animated_custom_value (GtkCssAnimatedStyle *animated,
+                                                                 int                     id,
+                                                                 GtkCssVariableValue    *value);
+GtkCssVariableValue *   gtk_css_animated_style_get_intrinsic_custom_value (GtkCssAnimatedStyle *style,
+                                                                 int                     id);
+
+GtkCssStyle *           gtk_css_animated_style_get_base_style   (GtkCssAnimatedStyle    *style);
+GtkCssStyle *           gtk_css_animated_style_get_parent_style (GtkCssAnimatedStyle    *style);
+GtkStyleProvider *      gtk_css_animated_style_get_provider     (GtkCssAnimatedStyle    *style);
+
 G_END_DECLS
 

gtk/gtkcssanimation.c

@@ -90,6 +90,9 @@ gtk_css_animation_apply_values (GtkStyleAnimation    *style_animation,
                                 GtkCssAnimatedStyle  *style)
 {
   GtkCssAnimation *animation = (GtkCssAnimation *)style_animation;
+  GtkCssStyle *base_style, *parent_style;
+  GtkStyleProvider *provider;
+  GtkCssKeyframes *resolved_keyframes;
   double progress;
   guint i;
 
@@ -99,19 +102,43 @@ gtk_css_animation_apply_values (GtkStyleAnimation    *style_animation,
   progress = gtk_css_animation_get_progress (animation);
   progress = _gtk_css_ease_value_transform (animation->ease, progress);
 
-  for (i = 0; i < _gtk_css_keyframes_get_n_properties (animation->keyframes); i++)
+  base_style = gtk_css_animated_style_get_base_style (style);
+  parent_style = gtk_css_animated_style_get_parent_style (style);
+  provider = gtk_css_animated_style_get_provider (style);
+  resolved_keyframes = _gtk_css_keyframes_compute (animation->keyframes,
+                                                   provider,
+                                                   base_style,
+                                                   parent_style);
+
+  for (i = 0; i < _gtk_css_keyframes_get_n_variables (resolved_keyframes); i++)
+    {
+      GtkCssVariableValue *value;
+      int variable_id;
+
+      variable_id = _gtk_css_keyframes_get_variable_id (resolved_keyframes, i);
+
+      value = _gtk_css_keyframes_get_variable (resolved_keyframes,
+                                               i,
+                                               progress,
+                                               gtk_css_animated_style_get_intrinsic_custom_value (style, variable_id));
+      gtk_css_animated_style_set_animated_custom_value (style, variable_id, value);
+    }
+
+  for (i = 0; i < _gtk_css_keyframes_get_n_properties (resolved_keyframes); i++)
     {
       GtkCssValue *value;
       guint property_id;
       
-      property_id = _gtk_css_keyframes_get_property_id (animation->keyframes, i);
+      property_id = _gtk_css_keyframes_get_property_id (resolved_keyframes, i);
 
-      value = _gtk_css_keyframes_get_value (animation->keyframes,
+      value = _gtk_css_keyframes_get_value (resolved_keyframes,
                                             i,
                                             progress,
                                             gtk_css_animated_style_get_intrinsic_value (style, property_id));
       gtk_css_animated_style_set_animated_value (style, property_id, value);
     }
+
+  _gtk_css_keyframes_unref (resolved_keyframes);
 }
 
 static gboolean

gtk/gtkcssarrayvalue.c

@@ -41,11 +41,12 @@ gtk_css_value_array_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_array_compute (GtkCssValue      *value,
-                             guint             property_id,
-                             GtkStyleProvider *provider,
-                             GtkCssStyle      *style,
-                             GtkCssStyle      *parent_style)
+gtk_css_value_array_compute (GtkCssValue       *value,
+                             guint              property_id,
+                             GtkStyleProvider  *provider,
+                             GtkCssStyle       *style,
+                             GtkCssStyle       *parent_style,
+                             GtkCssVariableSet *variables)
 {
   GtkCssValue *result;
   GtkCssValue *i_value;
@@ -54,7 +55,7 @@ gtk_css_value_array_compute (GtkCssValue      *value,
   result = NULL;
   for (i = 0; i < value->n_values; i++)
     {
-      i_value =  _gtk_css_value_compute (value->values[i], property_id, provider, style, parent_style);
+      i_value =  _gtk_css_value_compute (value->values[i], property_id, provider, style, parent_style, variables);
 
       if (result == NULL &&
 	  i_value != value->values[i])
@@ -342,6 +343,20 @@ gtk_css_value_array_get_dynamic_value (GtkCssValue *value,
   return result;
 }
 
+static gboolean
+gtk_css_value_array_contains_variables (const GtkCssValue *value)
+{
+  guint i;
+
+  for (i = 0; i < value->n_values; i++)
+    {
+      if (gtk_css_value_contains_variables (value->values[i]))
+        return TRUE;
+    }
+
+  return FALSE;
+}
+
 static void
 gtk_css_value_array_print (const GtkCssValue *value,
                            GString           *string)
@@ -370,6 +385,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_ARRAY = {
   gtk_css_value_array_transition,
   gtk_css_value_array_is_dynamic,
   gtk_css_value_array_get_dynamic_value,
+  gtk_css_value_array_contains_variables,
   gtk_css_value_array_print
 };
 

gtk/gtkcssbgsizevalue.c

@@ -41,11 +41,12 @@ gtk_css_value_bg_size_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_bg_size_compute (GtkCssValue      *value,
-                               guint             property_id,
-                               GtkStyleProvider *provider,
-                               GtkCssStyle      *style,
-                               GtkCssStyle      *parent_style)
+gtk_css_value_bg_size_compute (GtkCssValue       *value,
+                               guint              property_id,
+                               GtkStyleProvider  *provider,
+                               GtkCssStyle       *style,
+                               GtkCssStyle       *parent_style,
+                               GtkCssVariableSet *variables)
 {
   GtkCssValue *x, *y;
 
@@ -55,10 +56,10 @@ gtk_css_value_bg_size_compute (GtkCssValue      *value,
   x = y = NULL;
 
   if (value->x)
-    x = _gtk_css_value_compute (value->x, property_id, provider, style, parent_style);
+    x = _gtk_css_value_compute (value->x, property_id, provider, style, parent_style, variables);
 
   if (value->y)
-    y = _gtk_css_value_compute (value->y, property_id, provider, style, parent_style);
+    y = _gtk_css_value_compute (value->y, property_id, provider, style, parent_style, variables);
 
   if (x == value->x && y == value->y)
     {
@@ -160,6 +161,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_BG_SIZE = {
   gtk_css_value_bg_size_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_bg_size_print
 };
 

gtk/gtkcssbordervalue.c

@@ -42,11 +42,12 @@ gtk_css_value_border_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_border_compute (GtkCssValue      *value,
-                              guint             property_id,
-                              GtkStyleProvider *provider,
-                              GtkCssStyle      *style,
-                              GtkCssStyle      *parent_style)
+gtk_css_value_border_compute (GtkCssValue       *value,
+                              guint              property_id,
+                              GtkStyleProvider  *provider,
+                              GtkCssStyle       *style,
+                              GtkCssStyle       *parent_style,
+                              GtkCssVariableSet *variables)
 {
   GtkCssValue *values[4];
   GtkCssValue *computed;
@@ -57,7 +58,7 @@ gtk_css_value_border_compute (GtkCssValue      *value,
     {
       if (value->values[i])
         {
-          values[i] = _gtk_css_value_compute (value->values[i], property_id, provider, style, parent_style);
+          values[i] = _gtk_css_value_compute (value->values[i], property_id, provider, style, parent_style, variables);
           changed |= (values[i] != value->values[i]);
         }
       else
@@ -147,6 +148,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_BORDER = {
   gtk_css_value_border_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_border_print
 };
 

gtk/gtkcsscolorvalue.c

@@ -94,10 +94,11 @@ gtk_css_value_color_free (GtkCssValue *color)
 }
 
 static GtkCssValue *
-gtk_css_value_color_get_fallback (guint             property_id,
-                                  GtkStyleProvider *provider,
-                                  GtkCssStyle      *style,
-                                  GtkCssStyle      *parent_style)
+gtk_css_value_color_get_fallback (guint              property_id,
+                                  GtkStyleProvider  *provider,
+                                  GtkCssStyle       *style,
+                                  GtkCssStyle       *parent_style,
+                                  GtkCssVariableSet *variables)
 {
   switch (property_id)
     {
@@ -120,7 +121,8 @@ gtk_css_value_color_get_fallback (guint             property_id,
                                        property_id,
                                        provider,
                                        style,
-                                       parent_style);
+                                       parent_style,
+                                       variables);
       case GTK_CSS_PROPERTY_ICON_PALETTE:
         return _gtk_css_value_ref (style->core->color);
       default:
@@ -132,11 +134,12 @@ gtk_css_value_color_get_fallback (guint             property_id,
 }
 
 static GtkCssValue *
-gtk_css_value_color_compute (GtkCssValue      *value,
-                             guint             property_id,
-                             GtkStyleProvider *provider,
-                             GtkCssStyle      *style,
-                             GtkCssStyle      *parent_style)
+gtk_css_value_color_compute (GtkCssValue       *value,
+                             guint              property_id,
+                             GtkStyleProvider  *provider,
+                             GtkCssStyle       *style,
+                             GtkCssStyle       *parent_style,
+                             GtkCssVariableSet *variables)
 {
   GtkCssValue *resolved;
 
@@ -173,7 +176,7 @@ gtk_css_value_color_compute (GtkCssValue      *value,
     }
 
   if (resolved == NULL)
-    return gtk_css_value_color_get_fallback (property_id, provider, style, parent_style);
+    return gtk_css_value_color_get_fallback (property_id, provider, style, parent_style, variables);
 
   return resolved;
 }
@@ -293,6 +296,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_COLOR = {
   gtk_css_value_color_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_color_print
 };
 

gtk/gtkcsscornervalue.c

@@ -37,16 +37,17 @@ gtk_css_value_corner_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_corner_compute (GtkCssValue      *corner,
-                              guint             property_id,
-                              GtkStyleProvider *provider,
-                              GtkCssStyle      *style,
-                              GtkCssStyle      *parent_style)
+gtk_css_value_corner_compute (GtkCssValue       *corner,
+                              guint              property_id,
+                              GtkStyleProvider  *provider,
+                              GtkCssStyle       *style,
+                              GtkCssStyle       *parent_style,
+                              GtkCssVariableSet *variables)
 {
   GtkCssValue *x, *y;
 
-  x = _gtk_css_value_compute (corner->x, property_id, provider, style, parent_style);
-  y = _gtk_css_value_compute (corner->y, property_id, provider, style, parent_style);
+  x = _gtk_css_value_compute (corner->x, property_id, provider, style, parent_style, variables);
+  y = _gtk_css_value_compute (corner->y, property_id, provider, style, parent_style, variables);
   if (x == corner->x && y == corner->y)
     {
       _gtk_css_value_unref (x);
@@ -106,6 +107,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_CORNER = {
   gtk_css_value_corner_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_corner_print
 };
 

gtk/gtkcsscustompropertypool.c

@@ -0,0 +1,161 @@
+/*
+ * Copyright (C) 2023 GNOME Foundation Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Alice Mikhaylenko <alicem@gnome.org>
+ */
+
+#include "gtkcsscustompropertypoolprivate.h"
+
+struct _GtkCssCustomPropertyPool
+{
+  GObject parent_instance;
+
+  GArray *names;
+  GHashTable *name_mappings;
+};
+
+struct _GtkCssCustomPropertyName
+{
+  int ref_count;
+  char *name;
+};
+
+typedef struct _GtkCssCustomPropertyName GtkCssCustomPropertyName;
+
+static GtkCssCustomPropertyPool *instance = NULL;
+
+G_DEFINE_FINAL_TYPE (GtkCssCustomPropertyPool, gtk_css_custom_property_pool, G_TYPE_OBJECT)
+
+static void
+clear_custom_property_name (GtkCssCustomPropertyName *name)
+{
+  g_clear_pointer (&name->name, g_free);
+}
+
+static void
+gtk_css_custom_property_pool_finalize (GObject *object)
+{
+  GtkCssCustomPropertyPool *self = (GtkCssCustomPropertyPool *)object;
+
+  g_hash_table_unref (self->name_mappings);
+  g_array_unref (self->names);
+
+  G_OBJECT_CLASS (gtk_css_custom_property_pool_parent_class)->finalize (object);
+}
+
+static void
+gtk_css_custom_property_pool_class_init (GtkCssCustomPropertyPoolClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->finalize = gtk_css_custom_property_pool_finalize;
+}
+
+static void
+gtk_css_custom_property_pool_init (GtkCssCustomPropertyPool *self)
+{
+  self->name_mappings = g_hash_table_new (g_str_hash, g_str_equal);
+  self->names = g_array_new (FALSE, FALSE, sizeof (GtkCssCustomPropertyName));
+
+  g_array_set_clear_func (self->names, (GDestroyNotify) clear_custom_property_name);
+}
+
+GtkCssCustomPropertyPool *
+gtk_css_custom_property_pool_get (void)
+{
+  if (instance == NULL)
+    instance = g_object_new (GTK_TYPE_CSS_CUSTOM_PROPERTY_POOL, NULL);
+
+  return instance;
+}
+
+int
+gtk_css_custom_property_pool_add (GtkCssCustomPropertyPool *self,
+                                  const char               *str)
+{
+  GtkCssCustomPropertyName name;
+  int id;
+
+  id = gtk_css_custom_property_pool_lookup (self, str);
+  if (id > 0)
+    return gtk_css_custom_property_pool_ref (self, id);
+
+  name.ref_count = 1;
+  name.name = g_strdup (str);
+
+  // TODO reuse slots after they're gone
+  g_array_append_val (self->names, name);
+
+  id = self->names->len;
+
+  g_hash_table_insert (self->name_mappings, (char *) name.name, GINT_TO_POINTER (id));
+
+  return id;
+}
+
+int
+gtk_css_custom_property_pool_lookup (GtkCssCustomPropertyPool *self,
+                                     const char               *str)
+{
+  gpointer id;
+
+  id = g_hash_table_lookup (self->name_mappings, str);
+
+  return GPOINTER_TO_INT (id);
+}
+
+int
+gtk_css_custom_property_pool_ref (GtkCssCustomPropertyPool *self,
+                                  int                       id)
+{
+  GtkCssCustomPropertyName *name;
+
+  name = &g_array_index (self->names, GtkCssCustomPropertyName, id - 1);
+
+  name->ref_count++;
+
+  return id;
+}
+
+void
+gtk_css_custom_property_pool_unref (GtkCssCustomPropertyPool *self,
+                                    int                       id)
+{
+  GtkCssCustomPropertyName *name;
+
+  name = &g_array_index (self->names, GtkCssCustomPropertyName, id - 1);
+
+  g_assert (name->ref_count > 0);
+
+  name->ref_count--;
+
+  if (name->ref_count == 0)
+    {
+      g_hash_table_remove (self->name_mappings, name->name);
+      clear_custom_property_name (name);
+    }
+}
+
+const char *
+gtk_css_custom_property_pool_get_name (GtkCssCustomPropertyPool *self,
+                                       int                       id)
+{
+  GtkCssCustomPropertyName *name;
+
+  name = &g_array_index (self->names, GtkCssCustomPropertyName, id - 1);
+
+  return name->name;
+}

gtk/gtkcsscustompropertypoolprivate.h

@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2023 GNOME Foundation Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Alice Mikhaylenko <alicem@gnome.org>
+ */
+
+#pragma once
+
+#include <glib-object.h>
+
+G_BEGIN_DECLS
+
+#define GTK_TYPE_CSS_CUSTOM_PROPERTY_POOL (gtk_css_custom_property_pool_get_type())
+
+G_DECLARE_FINAL_TYPE (GtkCssCustomPropertyPool, gtk_css_custom_property_pool, GTK, CSS_CUSTOM_PROPERTY_POOL, GObject)
+
+GtkCssCustomPropertyPool *gtk_css_custom_property_pool_get      (void);
+
+int                       gtk_css_custom_property_pool_add      (GtkCssCustomPropertyPool *self,
+                                                                 const char               *str);
+int                       gtk_css_custom_property_pool_lookup   (GtkCssCustomPropertyPool *self,
+                                                                 const char               *str);
+const char *              gtk_css_custom_property_pool_get_name (GtkCssCustomPropertyPool *self,
+                                                                 int                       id);
+int                       gtk_css_custom_property_pool_ref      (GtkCssCustomPropertyPool *self,
+                                                                 int                       id);
+void                      gtk_css_custom_property_pool_unref    (GtkCssCustomPropertyPool *self,
+                                                                 int                       id);
+
+G_END_DECLS

gtk/gtkcsseasevalue.c

@@ -50,11 +50,12 @@ gtk_css_value_ease_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_ease_compute (GtkCssValue      *value,
-                            guint             property_id,
-                            GtkStyleProvider *provider,
-                            GtkCssStyle      *style,
-                            GtkCssStyle      *parent_style)
+gtk_css_value_ease_compute (GtkCssValue       *value,
+                            guint              property_id,
+                            GtkStyleProvider  *provider,
+                            GtkCssStyle       *style,
+                            GtkCssStyle       *parent_style,
+                            GtkCssVariableSet *variables)
 {
   return _gtk_css_value_ref (value);
 }
@@ -142,6 +143,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_EASE = {
   gtk_css_value_ease_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_ease_print
 };
 

gtk/gtkcssenumvalue.c

@@ -41,11 +41,12 @@ gtk_css_value_enum_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_enum_compute (GtkCssValue      *value,
-                            guint             property_id,
-                            GtkStyleProvider *provider,
-                            GtkCssStyle      *style,
-                            GtkCssStyle      *parent_style)
+gtk_css_value_enum_compute (GtkCssValue       *value,
+                            guint              property_id,
+                            GtkStyleProvider  *provider,
+                            GtkCssStyle       *style,
+                            GtkCssStyle       *parent_style,
+                            GtkCssVariableSet *variables)
 {
   return _gtk_css_value_ref (value);
 }
@@ -83,6 +84,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_BORDER_STYLE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -141,6 +143,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_BLEND_MODE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -229,11 +232,12 @@ gtk_css_font_size_get_default_px (GtkStyleProvider *provider,
 }
 
 static GtkCssValue *
-gtk_css_value_font_size_compute (GtkCssValue      *value,
-                                 guint             property_id,
-                                 GtkStyleProvider *provider,
-                                 GtkCssStyle      *style,
-                                 GtkCssStyle      *parent_style)
+gtk_css_value_font_size_compute (GtkCssValue       *value,
+                                 guint              property_id,
+                                 GtkStyleProvider  *provider,
+                                 GtkCssStyle       *style,
+                                 GtkCssStyle       *parent_style,
+                                 GtkCssVariableSet *variables)
 {
   double font_size;
 
@@ -292,6 +296,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_SIZE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -349,6 +354,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_STYLE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -396,11 +402,12 @@ _gtk_css_font_style_value_get (const GtkCssValue *value)
 #define LIGHTER -2
 
 static GtkCssValue *
-gtk_css_value_font_weight_compute (GtkCssValue      *value,
-                                   guint             property_id,
-                                   GtkStyleProvider *provider,
-                                   GtkCssStyle      *style,
-                                   GtkCssStyle      *parent_style)
+gtk_css_value_font_weight_compute (GtkCssValue       *value,
+                                   guint              property_id,
+                                   GtkStyleProvider  *provider,
+                                   GtkCssStyle       *style,
+                                   GtkCssStyle       *parent_style,
+                                   GtkCssVariableSet *variables)
 {
   PangoWeight new_weight;
   int parent_value;
@@ -448,6 +455,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_WEIGHT = {
   NULL,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -498,6 +506,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_STRETCH = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -555,6 +564,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_TEXT_DECORATION_STYLE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -606,6 +616,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_AREA = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -663,6 +674,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_DIRECTION = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -724,6 +736,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_PLAY_STATE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -780,6 +793,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FILL_MODE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -838,6 +852,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_ICON_STYLE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -895,6 +910,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_KERNING = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -952,6 +968,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_VARIANT_POSITION = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -1009,6 +1026,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_VARIANT_CAPS = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -1070,6 +1088,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_VARIANT_ALTERNATE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 
@@ -1178,6 +1197,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_TEXT_DECORATION_LINE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_text_decoration_line_value_print
 };
 
@@ -1277,6 +1297,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_VARIANT_LIGATURE = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_font_variant_ligature_value_print
 };
 
@@ -1385,6 +1406,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_VARIANT_NUMERIC = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_font_variant_numeric_value_print
 };
 
@@ -1490,6 +1512,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_VARIANT_EAST_ASIAN = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_font_variant_east_asian_value_print
 };
 
@@ -1579,6 +1602,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_TEXT_TRANSFORM = {
   gtk_css_value_enum_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_enum_print
 };
 

gtk/gtkcssfiltervalue.c

@@ -307,55 +307,56 @@ gtk_css_value_filter_free (GtkCssValue *value)
 
 /* returns TRUE if dest == src */
 static gboolean
-gtk_css_filter_compute (GtkCssFilter     *dest,
-                        GtkCssFilter     *src,
-                        guint             property_id,
-                        GtkStyleProvider *provider,
-                        GtkCssStyle      *style,
-                        GtkCssStyle      *parent_style)
+gtk_css_filter_compute (GtkCssFilter      *dest,
+                        GtkCssFilter      *src,
+                        guint              property_id,
+                        GtkStyleProvider  *provider,
+                        GtkCssStyle       *style,
+                        GtkCssStyle       *parent_style,
+                        GtkCssVariableSet *variables)
 {
   dest->type = src->type;
 
   switch (src->type)
     {
     case GTK_CSS_FILTER_BRIGHTNESS:
-      dest->brightness.value = _gtk_css_value_compute (src->brightness.value, property_id, provider, style, parent_style);
+      dest->brightness.value = _gtk_css_value_compute (src->brightness.value, property_id, provider, style, parent_style, variables);
       return dest->brightness.value == src->brightness.value;
 
     case GTK_CSS_FILTER_CONTRAST:
-      dest->contrast.value = _gtk_css_value_compute (src->contrast.value, property_id, provider, style, parent_style);
+      dest->contrast.value = _gtk_css_value_compute (src->contrast.value, property_id, provider, style, parent_style, variables);
       return dest->contrast.value == src->contrast.value;
 
     case GTK_CSS_FILTER_GRAYSCALE:
-      dest->grayscale.value = _gtk_css_value_compute (src->grayscale.value, property_id, provider, style, parent_style);
+      dest->grayscale.value = _gtk_css_value_compute (src->grayscale.value, property_id, provider, style, parent_style, variables);
       return dest->grayscale.value == src->grayscale.value;
 
     case GTK_CSS_FILTER_HUE_ROTATE:
-      dest->hue_rotate.value = _gtk_css_value_compute (src->hue_rotate.value, property_id, provider, style, parent_style);
+      dest->hue_rotate.value = _gtk_css_value_compute (src->hue_rotate.value, property_id, provider, style, parent_style, variables);
       return dest->hue_rotate.value == src->hue_rotate.value;
 
     case GTK_CSS_FILTER_INVERT:
-      dest->invert.value = _gtk_css_value_compute (src->invert.value, property_id, provider, style, parent_style);
+      dest->invert.value = _gtk_css_value_compute (src->invert.value, property_id, provider, style, parent_style, variables);
       return dest->invert.value == src->invert.value;
 
     case GTK_CSS_FILTER_OPACITY:
-      dest->opacity.value = _gtk_css_value_compute (src->opacity.value, property_id, provider, style, parent_style);
+      dest->opacity.value = _gtk_css_value_compute (src->opacity.value, property_id, provider, style, parent_style, variables);
       return dest->opacity.value == src->opacity.value;
 
     case GTK_CSS_FILTER_SATURATE:
-      dest->saturate.value = _gtk_css_value_compute (src->saturate.value, property_id, provider, style, parent_style);
+      dest->saturate.value = _gtk_css_value_compute (src->saturate.value, property_id, provider, style, parent_style, variables);
       return dest->saturate.value == src->saturate.value;
 
     case GTK_CSS_FILTER_SEPIA:
-      dest->sepia.value = _gtk_css_value_compute (src->sepia.value, property_id, provider, style, parent_style);
+      dest->sepia.value = _gtk_css_value_compute (src->sepia.value, property_id, provider, style, parent_style, variables);
       return dest->sepia.value == src->sepia.value;
 
     case GTK_CSS_FILTER_BLUR:
-      dest->blur.value = _gtk_css_value_compute (src->blur.value, property_id, provider, style, parent_style);
+      dest->blur.value = _gtk_css_value_compute (src->blur.value, property_id, provider, style, parent_style, variables);
       return dest->blur.value == src->blur.value;
 
     case GTK_CSS_FILTER_DROP_SHADOW:
-      dest->drop_shadow.value = _gtk_css_value_compute (src->drop_shadow.value, property_id, provider, style, parent_style);
+      dest->drop_shadow.value = _gtk_css_value_compute (src->drop_shadow.value, property_id, provider, style, parent_style, variables);
       return dest->drop_shadow.value == src->drop_shadow.value;
 
     case GTK_CSS_FILTER_NONE:
@@ -366,11 +367,12 @@ gtk_css_filter_compute (GtkCssFilter     *dest,
 }
 
 static GtkCssValue *
-gtk_css_value_filter_compute (GtkCssValue      *value,
-                              guint             property_id,
-                              GtkStyleProvider *provider,
-                              GtkCssStyle      *style,
-                              GtkCssStyle      *parent_style)
+gtk_css_value_filter_compute (GtkCssValue       *value,
+                              guint              property_id,
+                              GtkStyleProvider  *provider,
+                              GtkCssStyle       *style,
+                              GtkCssStyle       *parent_style,
+                              GtkCssVariableSet *variables)
 {
   GtkCssValue *result;
   gboolean changes;
@@ -390,7 +392,8 @@ gtk_css_value_filter_compute (GtkCssValue      *value,
                                           property_id,
                                           provider,
                                           style,
-                                          parent_style);
+                                          parent_style,
+                                          variables);
     }
 
   if (!changes)
@@ -720,6 +723,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FILTER = {
   gtk_css_value_filter_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_filter_print
 };
 

gtk/gtkcssfontfeaturesvalue.c

@@ -53,11 +53,12 @@ gtk_css_value_font_features_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_font_features_compute (GtkCssValue      *specified,
-                                     guint             property_id,
-                                     GtkStyleProvider *provider,
-                                     GtkCssStyle      *style,
-                                     GtkCssStyle      *parent_style)
+gtk_css_value_font_features_compute (GtkCssValue       *specified,
+                                     guint              property_id,
+                                     GtkStyleProvider  *provider,
+                                     GtkCssStyle       *style,
+                                     GtkCssStyle       *parent_style,
+                                     GtkCssVariableSet *variables)
 {
   return _gtk_css_value_ref (specified);
 }
@@ -162,6 +163,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_FEATURES = {
   gtk_css_value_font_features_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_font_features_print
 };
 

gtk/gtkcssfontvariationsvalue.c

@@ -52,11 +52,12 @@ gtk_css_value_font_variations_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_font_variations_compute (GtkCssValue      *specified,
-                                       guint             property_id,
-                                       GtkStyleProvider *provider,
-                                       GtkCssStyle      *style,
-                                       GtkCssStyle      *parent_style)
+gtk_css_value_font_variations_compute (GtkCssValue       *specified,
+                                       guint              property_id,
+                                       GtkStyleProvider  *provider,
+                                       GtkCssStyle       *style,
+                                       GtkCssStyle       *parent_style,
+                                       GtkCssVariableSet *variables)
 {
   return _gtk_css_value_ref (specified);
 }
@@ -163,6 +164,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_FONT_VARIATIONS = {
   gtk_css_value_font_variations_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_font_variations_print
 };
 

gtk/gtkcssimage.c

@@ -65,11 +65,12 @@ gtk_css_image_real_get_aspect_ratio (GtkCssImage *image)
 }
 
 static GtkCssImage *
-gtk_css_image_real_compute (GtkCssImage      *image,
-                            guint             property_id,
-                            GtkStyleProvider *provider,
-                            GtkCssStyle      *style,
-                            GtkCssStyle      *parent_style)
+gtk_css_image_real_compute (GtkCssImage       *image,
+                            guint              property_id,
+                            GtkStyleProvider  *provider,
+                            GtkCssStyle       *style,
+                            GtkCssStyle       *parent_style,
+                            GtkCssVariableSet *variables)
 {
   return g_object_ref (image);
 }
@@ -173,11 +174,12 @@ _gtk_css_image_get_aspect_ratio (GtkCssImage *image)
 }
 
 GtkCssImage *
-_gtk_css_image_compute (GtkCssImage      *image,
-                        guint             property_id,
-                        GtkStyleProvider *provider,
-                        GtkCssStyle      *style,
-                        GtkCssStyle      *parent_style)
+_gtk_css_image_compute (GtkCssImage       *image,
+                        guint              property_id,
+                        GtkStyleProvider  *provider,
+                        GtkCssStyle       *style,
+                        GtkCssStyle       *parent_style,
+                        GtkCssVariableSet *variables)
 {
   GtkCssImageClass *klass;
 
@@ -187,7 +189,7 @@ _gtk_css_image_compute (GtkCssImage      *image,
 
   klass = GTK_CSS_IMAGE_GET_CLASS (image);
 
-  return klass->compute (image, property_id, provider, style, parent_style);
+  return klass->compute (image, property_id, provider, style, parent_style, variables);
 }
 
 GtkCssImage *

gtk/gtkcssimageconic.c

@@ -313,11 +313,12 @@ gtk_css_image_conic_print (GtkCssImage *image,
 }
 
 static GtkCssImage *
-gtk_css_image_conic_compute (GtkCssImage      *image,
-                             guint             property_id,
-                             GtkStyleProvider *provider,
-                             GtkCssStyle      *style,
-                             GtkCssStyle      *parent_style)
+gtk_css_image_conic_compute (GtkCssImage       *image,
+                             guint              property_id,
+                             GtkStyleProvider  *provider,
+                             GtkCssStyle       *style,
+                             GtkCssStyle       *parent_style,
+                             GtkCssVariableSet *variables)
 {
   GtkCssImageConic *self = GTK_CSS_IMAGE_CONIC (image);
   GtkCssImageConic *copy;
@@ -325,8 +326,8 @@ gtk_css_image_conic_compute (GtkCssImage      *image,
 
   copy = g_object_new (GTK_TYPE_CSS_IMAGE_CONIC, NULL);
 
-  copy->center = _gtk_css_value_compute (self->center, property_id, provider, style, parent_style);
-  copy->rotation = _gtk_css_value_compute (self->rotation, property_id, provider, style, parent_style);
+  copy->center = _gtk_css_value_compute (self->center, property_id, provider, style, parent_style, variables);
+  copy->rotation = _gtk_css_value_compute (self->rotation, property_id, provider, style, parent_style, variables);
 
   copy->n_stops = self->n_stops;
   copy->color_stops = g_malloc (sizeof (GtkCssImageConicColorStop) * copy->n_stops);
@@ -335,11 +336,11 @@ gtk_css_image_conic_compute (GtkCssImage      *image,
       const GtkCssImageConicColorStop *stop = &self->color_stops[i];
       GtkCssImageConicColorStop *scopy = &copy->color_stops[i];
 
-      scopy->color = _gtk_css_value_compute (stop->color, property_id, provider, style, parent_style);
+      scopy->color = _gtk_css_value_compute (stop->color, property_id, provider, style, parent_style, variables);
 
       if (stop->offset)
         {
-          scopy->offset = _gtk_css_value_compute (stop->offset, property_id, provider, style, parent_style);
+          scopy->offset = _gtk_css_value_compute (stop->offset, property_id, provider, style, parent_style, variables);
         }
       else
         {

gtk/gtkcssimagecrossfade.c

@@ -399,11 +399,12 @@ gtk_css_image_cross_fade_print (GtkCssImage *image,
 }
 
 static GtkCssImage *
-gtk_css_image_cross_fade_compute (GtkCssImage      *image,
-                                  guint             property_id,
-                                  GtkStyleProvider *provider,
-                                  GtkCssStyle      *style,
-                                  GtkCssStyle      *parent_style)
+gtk_css_image_cross_fade_compute (GtkCssImage       *image,
+                                  guint              property_id,
+                                  GtkStyleProvider  *provider,
+                                  GtkCssStyle       *style,
+                                  GtkCssStyle       *parent_style,
+                                  GtkCssVariableSet *variables)
 {
   GtkCssImageCrossFade *self = GTK_CSS_IMAGE_CROSS_FADE (image);
   GtkCssImageCrossFade *result;
@@ -418,7 +419,7 @@ gtk_css_image_cross_fade_compute (GtkCssImage      *image,
       gtk_css_image_cross_fade_add (result,
                                     entry->has_progress,
                                     entry->progress,
-                                    _gtk_css_image_compute (entry->image, property_id, provider, style, parent_style));
+                                    _gtk_css_image_compute (entry->image, property_id, provider, style, parent_style, variables));
     }
 
   return GTK_CSS_IMAGE (result);

gtk/gtkcssimagefallback.c

@@ -133,11 +133,12 @@ gtk_css_image_fallback_dispose (GObject *object)
 
 
 static GtkCssImage *
-gtk_css_image_fallback_compute (GtkCssImage      *image,
-                                guint             property_id,
-                                GtkStyleProvider *provider,
-                                GtkCssStyle      *style,
-                                GtkCssStyle      *parent_style)
+gtk_css_image_fallback_compute (GtkCssImage       *image,
+                                guint              property_id,
+                                GtkStyleProvider  *provider,
+                                GtkCssStyle       *style,
+                                GtkCssStyle       *parent_style,
+                                GtkCssVariableSet *variables)
 {
   GtkCssImageFallback *fallback = GTK_CSS_IMAGE_FALLBACK (image);
   GtkCssImageFallback *copy;
@@ -152,7 +153,8 @@ gtk_css_image_fallback_compute (GtkCssImage      *image,
                                                  property_id,
                                                  provider,
                                                  style,
-                                                 parent_style);
+                                                 parent_style,
+                                                 variables);
 
       /* image($color) that didn't change */
       if (computed_color && !fallback->images &&
@@ -168,7 +170,8 @@ gtk_css_image_fallback_compute (GtkCssImage      *image,
                                                     property_id,
                                                     provider,
                                                     style,
-                                                    parent_style);
+                                                    parent_style,
+                                                    variables);
 
           if (gtk_css_image_is_invalid (copy->images[i]))
             continue;

gtk/gtkcssimageicontheme.c

@@ -138,11 +138,12 @@ gtk_css_image_icon_theme_print (GtkCssImage *image,
 }
 
 static GtkCssImage *
-gtk_css_image_icon_theme_compute (GtkCssImage      *image,
-                                  guint             property_id,
-                                  GtkStyleProvider *provider,
-                                  GtkCssStyle      *style,
-                                  GtkCssStyle      *parent_style)
+gtk_css_image_icon_theme_compute (GtkCssImage       *image,
+                                  guint              property_id,
+                                  GtkStyleProvider  *provider,
+                                  GtkCssStyle       *style,
+                                  GtkCssStyle       *parent_style,
+                                  GtkCssVariableSet *variables)
 {
   GtkCssImageIconTheme *icon_theme = GTK_CSS_IMAGE_ICON_THEME (image);
   GtkCssImageIconTheme *copy;

gtk/gtkcssimagelinear.c

@@ -488,11 +488,12 @@ gtk_css_image_linear_print (GtkCssImage *image,
 }
 
 static GtkCssImage *
-gtk_css_image_linear_compute (GtkCssImage      *image,
-                              guint             property_id,
-                              GtkStyleProvider *provider,
-                              GtkCssStyle      *style,
-                              GtkCssStyle      *parent_style)
+gtk_css_image_linear_compute (GtkCssImage       *image,
+                              guint              property_id,
+                              GtkStyleProvider  *provider,
+                              GtkCssStyle       *style,
+                              GtkCssStyle       *parent_style,
+                              GtkCssVariableSet *variables)
 {
   GtkCssImageLinear *linear = GTK_CSS_IMAGE_LINEAR (image);
   GtkCssImageLinear *copy;
@@ -503,7 +504,7 @@ gtk_css_image_linear_compute (GtkCssImage      *image,
   copy->side = linear->side;
 
   if (linear->angle)
-    copy->angle = _gtk_css_value_compute (linear->angle, property_id, provider, style, parent_style);
+    copy->angle = _gtk_css_value_compute (linear->angle, property_id, provider, style, parent_style, variables);
 
   copy->n_stops = linear->n_stops;
   copy->color_stops = g_malloc (sizeof (GtkCssImageLinearColorStop) * copy->n_stops);
@@ -512,11 +513,11 @@ gtk_css_image_linear_compute (GtkCssImage      *image,
       const GtkCssImageLinearColorStop *stop = &linear->color_stops[i];
       GtkCssImageLinearColorStop *scopy = &copy->color_stops[i];
 
-      scopy->color = _gtk_css_value_compute (stop->color, property_id, provider, style, parent_style);
+      scopy->color = _gtk_css_value_compute (stop->color, property_id, provider, style, parent_style, variables);
 
       if (stop->offset)
         {
-          scopy->offset = _gtk_css_value_compute (stop->offset, property_id, provider, style, parent_style);
+          scopy->offset = _gtk_css_value_compute (stop->offset, property_id, provider, style, parent_style, variables);
         }
       else
         {

gtk/gtkcssimagepaintable.c

@@ -96,11 +96,12 @@ gtk_css_image_paintable_get_static_image (GtkCssImage *image)
 }
 
 static GtkCssImage *
-gtk_css_image_paintable_compute (GtkCssImage      *image,
-                                 guint             property_id,
-                                 GtkStyleProvider *provider,
-                                 GtkCssStyle      *style,
-                                 GtkCssStyle      *parent_style)
+gtk_css_image_paintable_compute (GtkCssImage       *image,
+                                 guint              property_id,
+                                 GtkStyleProvider  *provider,
+                                 GtkCssStyle       *style,
+                                 GtkCssStyle       *parent_style,
+                                 GtkCssVariableSet *variables)
 {
   return gtk_css_image_paintable_get_static_image (image);
 }

gtk/gtkcssimageprivate.h

@@ -26,6 +26,7 @@
 #include "gtk/css/gtkcsstokenizerprivate.h"
 #include "gtk/css/gtkcssparserprivate.h"
 #include "gtk/gtkcsstypesprivate.h"
+#include "gtk/gtkcssvariablesetprivate.h"
 #include "gtk/gtksnapshot.h"
 #include "gtk/gtkstyleprovider.h"
 
@@ -62,7 +63,8 @@ struct _GtkCssImageClass
                                                     guint                       property_id,
                                                     GtkStyleProvider           *provider,
                                                     GtkCssStyle                *style,
-                                                    GtkCssStyle                *parent_style);
+                                                    GtkCssStyle                *parent_style,
+                                                    GtkCssVariableSet          *variables);
   /* compare two images for equality */
   gboolean     (* equal)                           (GtkCssImage                *image1,
                                                     GtkCssImage                *image2);
@@ -106,7 +108,8 @@ GtkCssImage *  _gtk_css_image_compute              (GtkCssImage                *
                                                     guint                       property_id,
                                                     GtkStyleProvider           *provider,
                                                     GtkCssStyle                *style,
-                                                    GtkCssStyle                *parent_style);
+                                                    GtkCssStyle                *parent_style,
+                                                    GtkCssVariableSet          *variables);
 gboolean       _gtk_css_image_equal                (GtkCssImage                *image1,
                                                     GtkCssImage                *image2) G_GNUC_PURE;
 GtkCssImage *  _gtk_css_image_transition           (GtkCssImage                *start,

gtk/gtkcssimageradial.c

@@ -489,11 +489,12 @@ gtk_css_image_radial_print (GtkCssImage *image,
 }
 
 static GtkCssImage *
-gtk_css_image_radial_compute (GtkCssImage      *image,
-                              guint             property_id,
-                              GtkStyleProvider *provider,
-                              GtkCssStyle      *style,
-                              GtkCssStyle      *parent_style)
+gtk_css_image_radial_compute (GtkCssImage       *image,
+                              guint              property_id,
+                              GtkStyleProvider  *provider,
+                              GtkCssStyle       *style,
+                              GtkCssStyle       *parent_style,
+                              GtkCssVariableSet *variables)
 {
   GtkCssImageRadial *radial = GTK_CSS_IMAGE_RADIAL (image);
   GtkCssImageRadial *copy;
@@ -504,13 +505,13 @@ gtk_css_image_radial_compute (GtkCssImage      *image,
   copy->circle = radial->circle;
   copy->size = radial->size;
 
-  copy->position = _gtk_css_value_compute (radial->position, property_id, provider, style, parent_style);
+  copy->position = _gtk_css_value_compute (radial->position, property_id, provider, style, parent_style, variables);
 
   if (radial->sizes[0])
-    copy->sizes[0] = _gtk_css_value_compute (radial->sizes[0], property_id, provider, style, parent_style);
+    copy->sizes[0] = _gtk_css_value_compute (radial->sizes[0], property_id, provider, style, parent_style, variables);
 
   if (radial->sizes[1])
-    copy->sizes[1] = _gtk_css_value_compute (radial->sizes[1], property_id, provider, style, parent_style);
+    copy->sizes[1] = _gtk_css_value_compute (radial->sizes[1], property_id, provider, style, parent_style, variables);
 
   copy->n_stops = radial->n_stops;
   copy->color_stops = g_malloc (sizeof (GtkCssImageRadialColorStop) * copy->n_stops);
@@ -519,11 +520,11 @@ gtk_css_image_radial_compute (GtkCssImage      *image,
       const GtkCssImageRadialColorStop *stop = &radial->color_stops[i];
       GtkCssImageRadialColorStop *scopy = &copy->color_stops[i];
 
-      scopy->color = _gtk_css_value_compute (stop->color, property_id, provider, style, parent_style);
+      scopy->color = _gtk_css_value_compute (stop->color, property_id, provider, style, parent_style, variables);
 
       if (stop->offset)
         {
-          scopy->offset = _gtk_css_value_compute (stop->offset, property_id, provider, style, parent_style);
+          scopy->offset = _gtk_css_value_compute (stop->offset, property_id, provider, style, parent_style, variables);
         }
       else
         {

gtk/gtkcssimagerecolor.c

@@ -200,11 +200,12 @@ gtk_css_image_recolor_snapshot (GtkCssImage *image,
 }
 
 static GtkCssImage *
-gtk_css_image_recolor_compute (GtkCssImage      *image,
-                               guint             property_id,
-                               GtkStyleProvider *provider,
-                               GtkCssStyle      *style,
-                               GtkCssStyle      *parent_style)
+gtk_css_image_recolor_compute (GtkCssImage       *image,
+                               guint              property_id,
+                               GtkStyleProvider  *provider,
+                               GtkCssStyle       *style,
+                               GtkCssStyle       *parent_style,
+                               GtkCssVariableSet *variables)
 {
   GtkCssImageRecolor *recolor = GTK_CSS_IMAGE_RECOLOR (image);
   GtkCssValue *palette;
@@ -215,7 +216,7 @@ gtk_css_image_recolor_compute (GtkCssImage      *image,
   scale = gtk_style_provider_get_scale (provider);
 
   if (recolor->palette)
-    palette = _gtk_css_value_compute (recolor->palette, property_id, provider, style, parent_style);
+    palette = _gtk_css_value_compute (recolor->palette, property_id, provider, style, parent_style, variables);
   else
     palette = _gtk_css_value_ref (style->core->icon_palette);
 

gtk/gtkcssimagescaled.c

@@ -97,11 +97,12 @@ gtk_css_image_scaled_dispose (GObject *object)
 
 
 static GtkCssImage *
-gtk_css_image_scaled_compute (GtkCssImage      *image,
-                              guint             property_id,
-                              GtkStyleProvider *provider,
-                              GtkCssStyle      *style,
-                              GtkCssStyle      *parent_style)
+gtk_css_image_scaled_compute (GtkCssImage       *image,
+                              guint              property_id,
+                              GtkStyleProvider  *provider,
+                              GtkCssStyle       *style,
+                              GtkCssStyle       *parent_style,
+                              GtkCssVariableSet *variables)
 {
   GtkCssImageScaled *scaled = GTK_CSS_IMAGE_SCALED (image);
   int scale;
@@ -137,7 +138,8 @@ gtk_css_image_scaled_compute (GtkCssImage      *image,
                                            property_id,
                                            provider,
                                            style,
-                                           parent_style);
+                                           parent_style,
+                                           variables);
   res->scales[0] = scaled->scales[best];
 
   return GTK_CSS_IMAGE (res);

gtk/gtkcssimageurl.c

@@ -112,11 +112,12 @@ gtk_css_image_url_snapshot (GtkCssImage *image,
 }
 
 static GtkCssImage *
-gtk_css_image_url_compute (GtkCssImage      *image,
-                           guint             property_id,
-                           GtkStyleProvider *provider,
-                           GtkCssStyle      *style,
-                           GtkCssStyle      *parent_style)
+gtk_css_image_url_compute (GtkCssImage       *image,
+                           guint              property_id,
+                           GtkStyleProvider  *provider,
+                           GtkCssStyle       *style,
+                           GtkCssStyle       *parent_style,
+                           GtkCssVariableSet *variables)
 {
   GtkCssImageUrl *url = GTK_CSS_IMAGE_URL (image);
   GtkCssImage *copy;

gtk/gtkcssimagevalue.c

@@ -34,11 +34,12 @@ gtk_css_value_image_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_image_compute (GtkCssValue      *value,
-                             guint             property_id,
-                             GtkStyleProvider *provider,
-                             GtkCssStyle      *style,
-                             GtkCssStyle      *parent_style)
+gtk_css_value_image_compute (GtkCssValue       *value,
+                             guint              property_id,
+                             GtkStyleProvider  *provider,
+                             GtkCssStyle       *style,
+                             GtkCssStyle       *parent_style,
+                             GtkCssVariableSet *variables)
 {
   GtkCssImage *image, *computed;
   
@@ -47,7 +48,7 @@ gtk_css_value_image_compute (GtkCssValue      *value,
   if (image == NULL)
     return _gtk_css_value_ref (value);
 
-  computed = _gtk_css_image_compute (image, property_id, provider, style, parent_style);
+  computed = _gtk_css_image_compute (image, property_id, provider, style, parent_style, variables);
 
   if (computed == image)
     {
@@ -130,6 +131,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_IMAGE = {
   gtk_css_value_image_transition,
   gtk_css_value_image_is_dynamic,
   gtk_css_value_image_get_dynamic_value,
+  NULL,
   gtk_css_value_image_print
 };
 

gtk/gtkcssinheritvalue.c

@@ -34,11 +34,12 @@ gtk_css_value_inherit_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_inherit_compute (GtkCssValue      *value,
-                               guint             property_id,
-                               GtkStyleProvider *provider,
-                               GtkCssStyle      *style,
-                               GtkCssStyle      *parent_style)
+gtk_css_value_inherit_compute (GtkCssValue       *value,
+                               guint              property_id,
+                               GtkStyleProvider  *provider,
+                               GtkCssStyle       *style,
+                               GtkCssStyle       *parent_style,
+                               GtkCssVariableSet *variables)
 {
   if (parent_style)
     {
@@ -50,7 +51,8 @@ gtk_css_value_inherit_compute (GtkCssValue      *value,
                                      property_id,
                                      provider,
                                      style,
-                                     parent_style);
+                                     parent_style,
+                                     variables);
     }
 }
 
@@ -85,6 +87,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_INHERIT = {
   gtk_css_value_inherit_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_inherit_print
 };
 

gtk/gtkcssinitialvalue.c

@@ -38,11 +38,12 @@ gtk_css_value_initial_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_initial_compute (GtkCssValue      *value,
-                               guint             property_id,
-                               GtkStyleProvider *provider,
-                               GtkCssStyle      *style,
-                               GtkCssStyle      *parent_style)
+gtk_css_value_initial_compute (GtkCssValue       *value,
+                               guint              property_id,
+                               GtkStyleProvider  *provider,
+                               GtkCssStyle       *style,
+                               GtkCssStyle       *parent_style,
+                               GtkCssVariableSet *variables)
 {
   GtkSettings *settings;
 
@@ -75,7 +76,8 @@ gtk_css_value_initial_compute (GtkCssValue      *value,
                                  property_id,
                                  provider,
                                  style,
-                                 parent_style);
+                                 parent_style,
+                                 variables);
 }
 
 static gboolean
@@ -109,6 +111,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_INITIAL = {
   gtk_css_value_initial_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_initial_print
 };
 
@@ -135,5 +138,6 @@ _gtk_css_initial_value_new_compute (guint             property_id,
                                         property_id,
                                         provider,
                                         style,
-                                        parent_style);
+                                        parent_style,
+                                        NULL);
 }

gtk/gtkcsskeyframes.c

@@ -21,6 +21,8 @@
 
 #include "gtkcssstyleprivate.h"
 #include "gtkcssarrayvalueprivate.h"
+#include "gtkcsscustompropertypoolprivate.h"
+#include "gtkcssreferencevalueprivate.h"
 #include "gtkcssshorthandpropertyprivate.h"
 #include "gtkcssstylepropertyprivate.h"
 #include "gtkstylepropertyprivate.h"
@@ -31,12 +33,15 @@
 #include <string.h>
 
 struct _GtkCssKeyframes {
-  int ref_count;                /* ref count */
-  int n_keyframes;              /* number of keyframes (at least 2 for 0% and 100% */
-  double *keyframe_progress;    /* ordered array of n_keyframes of [0..1] */
-  int n_properties;             /* number of properties used by keyframes */
-  guint *property_ids;          /* ordered array of n_properties property ids */
-  GtkCssValue **values;         /* 2D array: n_keyframes * n_properties of (value or NULL) for all the keyframes */
+  int ref_count;                 /* ref count */
+  int n_keyframes;               /* number of keyframes (at least 2 for 0% and 100% */
+  double *keyframe_progress;     /* ordered array of n_keyframes of [0..1] */
+  int n_properties;              /* number of properties used by keyframes */
+  guint *property_ids;           /* ordered array of n_properties property ids */
+  GtkCssValue **values;          /* 2D array: n_keyframes * n_properties of (value or NULL) for all the keyframes */
+  GtkCssVariableSet **variables; /* array of variable sets for each keyframe */
+  int *variable_ids;             /* ordered array of variable ids */
+  int n_variables;               /* number of variable used by keyframes */
 };
 
 #define KEYFRAMES_VALUE(keyframes, k, p) ((keyframes)->values[(k) * (keyframes)->n_properties + (p)])
@@ -72,8 +77,13 @@ _gtk_css_keyframes_unref (GtkCssKeyframes *keyframes)
           _gtk_css_value_unref (KEYFRAMES_VALUE (keyframes, k, p));
           KEYFRAMES_VALUE (keyframes, k, p) = NULL;
         }
+
+      if (keyframes->variables && keyframes->variables[k])
+        gtk_css_variable_set_unref (keyframes->variables[k]);
     }
   g_free (keyframes->values);
+  g_free (keyframes->variables);
+  g_free (keyframes->variable_ids);
 
   g_free (keyframes);
 }
@@ -120,6 +130,9 @@ gtk_css_keyframes_add_keyframe (GtkCssKeyframes *keyframes,
       memset (&KEYFRAMES_VALUE (keyframes, k, 0), 0, size);
     }
 
+  if (keyframes->variables)
+    keyframes->variables = g_realloc (keyframes->variables, sizeof (GtkCssVariableSet *) * keyframes->n_keyframes);
+
   return k;
 }
 
@@ -173,6 +186,26 @@ gtk_css_keyframes_lookup_property (GtkCssKeyframes *keyframes,
   return p;
 }
 
+static void
+gtk_css_keyframes_register_variable (GtkCssKeyframes *keyframes,
+                                     int              variable_id)
+{
+  guint p;
+
+  for (p = 0; p < keyframes->n_variables; p++)
+    {
+      if (keyframes->variable_ids[p] == variable_id)
+        return;
+      else if (keyframes->variable_ids[p] > variable_id)
+        break;
+    }
+
+  keyframes->n_variables++;
+  keyframes->variable_ids = g_realloc (keyframes->variable_ids, sizeof (int) * keyframes->n_variables);
+  memmove (keyframes->variable_ids + p + 1, keyframes->variable_ids + p, sizeof (int) * (keyframes->n_variables - p - 1));
+  keyframes->variable_ids[p] = variable_id;
+}
+
 static GtkCssKeyframes *
 gtk_css_keyframes_alloc (void)
 {
@@ -235,6 +268,44 @@ gtk_css_keyframes_parse_declaration (GtkCssKeyframes *keyframes,
       return FALSE;
     }
 
+  /* This is a custom property */
+  if (name[0] == '-' && name[1] == '-')
+    {
+      GtkCssVariableValue *var_value;
+      GtkCssCustomPropertyPool *pool;
+      int id;
+
+      if (!gtk_css_parser_try_token (parser, GTK_CSS_TOKEN_COLON))
+        {
+          gtk_css_parser_error_syntax (parser, "Expected a ':'");
+          g_free (name);
+          return FALSE;
+        }
+
+      var_value = gtk_css_parser_parse_value_into_token_stream (parser);
+      if (var_value == NULL)
+        {
+          g_free (name);
+          return FALSE;
+        }
+
+      if (!keyframes->variables)
+        keyframes->variables = g_new0 (GtkCssVariableSet *, keyframes->n_keyframes);
+
+      if (!keyframes->variables[k])
+        keyframes->variables[k] = gtk_css_variable_set_new ();
+
+      pool = gtk_css_custom_property_pool_get ();
+      id = gtk_css_custom_property_pool_add (pool, name);
+      gtk_css_keyframes_register_variable (keyframes, id);
+
+      gtk_css_variable_set_add (keyframes->variables[k], id, var_value);
+
+      gtk_css_custom_property_pool_unref (pool, id);
+
+      return TRUE;
+    }
+
   property = _gtk_style_property_lookup (name);
   if (property == NULL)
     {
@@ -251,9 +322,53 @@ gtk_css_keyframes_parse_declaration (GtkCssKeyframes *keyframes,
       return FALSE;
     }
 
-  value = _gtk_style_property_parse_value (property, parser);
-  if (value == NULL)
-    return FALSE;
+  if (gtk_css_parser_has_references (parser))
+    {
+      GtkCssVariableValue *var_value;
+
+      var_value = gtk_css_parser_parse_value_into_token_stream (parser);
+      if (var_value == NULL)
+        return FALSE;
+
+      if (GTK_IS_CSS_SHORTHAND_PROPERTY (property))
+        {
+          GtkCssShorthandProperty *shorthand = GTK_CSS_SHORTHAND_PROPERTY (property);
+          guint i, n;
+          GtkCssValue **values;
+
+          n = _gtk_css_shorthand_property_get_n_subproperties (shorthand);
+
+          values = g_new (GtkCssValue *, n);
+
+          for (i = 0; i < n; i++)
+            {
+              GtkCssValue *child =
+                _gtk_css_reference_value_new (property,
+                                              var_value,
+                                              gtk_css_parser_get_file (parser));
+              _gtk_css_reference_value_set_subproperty (child, i);
+
+              values[i] = _gtk_css_array_value_get_nth (child, i);
+            }
+
+          value = _gtk_css_array_value_new_from_array (values, n);
+          g_free (values);
+        }
+      else
+        {
+          value = _gtk_css_reference_value_new (property,
+                                                var_value,
+                                                gtk_css_parser_get_file (parser));
+        }
+
+      gtk_css_variable_value_unref (var_value);
+    }
+  else
+    {
+      value = _gtk_style_property_parse_value (property, parser);
+      if (value == NULL)
+        return FALSE;
+    }
 
   if (!gtk_css_parser_has_token (parser, GTK_CSS_TOKEN_EOF))
     {
@@ -314,6 +429,9 @@ gtk_css_keyframes_parse_block (GtkCssKeyframes *keyframes,
       gtk_css_parser_end_block (parser);
     }
 
+  if (keyframes->variables && keyframes->variables[k])
+    gtk_css_variable_set_resolve_cycles (keyframes->variables[k]);
+
   gtk_css_parser_end_block (parser);
 
   return TRUE;
@@ -461,10 +579,27 @@ _gtk_css_keyframes_compute (GtkCssKeyframes  *keyframes,
                                                                       resolved->property_ids[p],
                                                                       provider,
                                                                       style,
-                                                                      parent_style);
+                                                                      parent_style,
+                                                                      keyframes->variables ? keyframes->variables[k] : NULL);
         }
     }
 
+  if (keyframes->variables)
+    {
+      resolved->variables = g_new0 (GtkCssVariableSet *, resolved->n_keyframes);
+
+      for (k = 0; k < resolved->n_keyframes; k++)
+        {
+          if (keyframes->variables[k])
+            resolved->variables[k] = gtk_css_variable_set_ref (keyframes->variables[k]);
+        }
+    }
+  else
+    resolved->variables = NULL;
+
+  resolved->variable_ids = g_memdup2 (keyframes->variable_ids, keyframes->n_variables * sizeof (int));
+  resolved->n_variables = keyframes->n_variables;
+
   return resolved;
 }
 
@@ -540,3 +675,78 @@ _gtk_css_keyframes_get_value (GtkCssKeyframes *keyframes,
   return result;
 }
 
+guint
+_gtk_css_keyframes_get_n_variables (GtkCssKeyframes *keyframes)
+{
+  g_return_val_if_fail (keyframes != NULL, 0);
+
+  return keyframes->n_variables;
+}
+
+int
+_gtk_css_keyframes_get_variable_id (GtkCssKeyframes *keyframes,
+                                    guint            id)
+{
+  g_return_val_if_fail (keyframes != NULL, 0);
+  g_return_val_if_fail (id < keyframes->n_variables, 0);
+
+  return keyframes->variable_ids[id];
+}
+
+GtkCssVariableValue *
+_gtk_css_keyframes_get_variable (GtkCssKeyframes     *keyframes,
+                                 guint                id,
+                                 double               progress,
+                                 GtkCssVariableValue *default_value)
+{
+  GtkCssVariableValue *start_value, *end_value, *result;
+  double start_progress, end_progress;
+  int variable_id;
+  guint k;
+
+  g_return_val_if_fail (keyframes != NULL, 0);
+  g_return_val_if_fail (id < keyframes->n_variables, 0);
+
+  start_value = default_value;
+  start_progress = 0.0;
+  end_value = default_value;
+  end_progress = 1.0;
+
+  variable_id = keyframes->variable_ids[id];
+
+  for (k = 0; k < keyframes->n_keyframes; k++)
+    {
+      GtkCssVariableValue *value = gtk_css_variable_set_lookup (keyframes->variables[k], variable_id, NULL);
+
+      if (value == NULL)
+        continue;
+
+      if (keyframes->keyframe_progress[k] == progress)
+        {
+          return gtk_css_variable_value_ref (value);
+        }
+      else if (keyframes->keyframe_progress[k] < progress)
+        {
+          start_value = value;
+          start_progress = keyframes->keyframe_progress[k];
+        }
+      else
+        {
+          end_value = value;
+          end_progress = keyframes->keyframe_progress[k];
+          break;
+        }
+    }
+
+  progress = (progress - start_progress) / (end_progress - start_progress);
+
+  result = gtk_css_variable_value_transition (start_value,
+                                              end_value,
+                                              progress);
+
+  /* XXX: Dear spec, what's the correct thing to do here? */
+  if (result == NULL)
+    return start_value ? gtk_css_variable_value_ref (start_value) : NULL;
+
+  return result;
+}

gtk/gtkcsskeyframesprivate.h

@@ -50,5 +50,13 @@ GtkCssValue *       _gtk_css_keyframes_get_value              (GtkCssKeyframes
                                                                double                  progress,
                                                                GtkCssValue            *default_value);
 
+guint               _gtk_css_keyframes_get_n_variables        (GtkCssKeyframes        *keyframes);
+int                 _gtk_css_keyframes_get_variable_id        (GtkCssKeyframes        *keyframes,
+                                                               guint                   id);
+GtkCssVariableValue *_gtk_css_keyframes_get_variable          (GtkCssKeyframes        *keyframes,
+                                                               guint                   id,
+                                                               double                  progress,
+                                                               GtkCssVariableValue    *default_value);
+
 G_END_DECLS
 

gtk/gtkcsslineheightvalue.c

@@ -39,15 +39,16 @@ gtk_css_value_line_height_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_line_height_compute (GtkCssValue      *value,
-                                   guint             property_id,
-                                   GtkStyleProvider *provider,
-                                   GtkCssStyle      *style,
-                                   GtkCssStyle      *parent_style)
+gtk_css_value_line_height_compute (GtkCssValue       *value,
+                                   guint              property_id,
+                                   GtkStyleProvider  *provider,
+                                   GtkCssStyle       *style,
+                                   GtkCssStyle       *parent_style,
+                                   GtkCssVariableSet *variables)
 {
   GtkCssValue *height;
 
-  height = _gtk_css_value_compute (value->height, property_id, provider, style, parent_style);
+  height = _gtk_css_value_compute (value->height, property_id, provider, style, parent_style, variables);
 
   if (gtk_css_number_value_get_dimension (height) == GTK_CSS_DIMENSION_PERCENTAGE)
     {
@@ -113,6 +114,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_LINE_HEIGHT = {
   gtk_css_value_line_height_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_line_height_print
 };
 

gtk/gtkcsslookup.c

@@ -19,6 +19,7 @@
 
 #include "gtkcsslookupprivate.h"
 
+#include "gtkcsscustompropertypoolprivate.h"
 #include "gtkcssstylepropertyprivate.h"
 #include "gtkcsstypesprivate.h"
 #include "gtkprivatetypebuiltins.h"
@@ -36,6 +37,9 @@ void
 _gtk_css_lookup_destroy (GtkCssLookup *lookup)
 {
   _gtk_bitmask_free (lookup->set_values);
+
+  if (lookup->custom_values)
+    g_hash_table_unref (lookup->custom_values);
 }
 
 gboolean
@@ -74,3 +78,17 @@ _gtk_css_lookup_set (GtkCssLookup  *lookup,
   lookup->values[id].section = section;
   lookup->set_values = _gtk_bitmask_set (lookup->set_values, id, TRUE);
 }
+
+void
+_gtk_css_lookup_set_custom (GtkCssLookup        *lookup,
+                            int                  id,
+                            GtkCssVariableValue *value)
+{
+  gtk_internal_return_if_fail (lookup != NULL);
+
+  if (!lookup->custom_values)
+    lookup->custom_values = g_hash_table_new (g_direct_hash, g_direct_equal);
+
+  if (!g_hash_table_contains (lookup->custom_values, GINT_TO_POINTER (id)))
+    g_hash_table_replace (lookup->custom_values, GINT_TO_POINTER (id), value);
+}

gtk/gtkcsslookupprivate.h

@@ -23,6 +23,8 @@
 #include "gtk/gtkcssstaticstyleprivate.h"
 
 #include "gtk/css/gtkcsssection.h"
+#include "gtk/css/gtkcsstokenizerprivate.h"
+#include "gtk/css/gtkcssvariablevalueprivate.h"
 
 
 G_BEGIN_DECLS
@@ -37,6 +39,7 @@ typedef struct {
 struct _GtkCssLookup {
   GtkBitmask *set_values;
   GtkCssLookupValue  values[GTK_CSS_PROPERTY_N_PROPERTIES];
+  GHashTable *custom_values;
 };
 
 void                    _gtk_css_lookup_init                    (GtkCssLookup               *lookup);
@@ -47,6 +50,9 @@ void                    _gtk_css_lookup_set                     (GtkCssLookup
                                                                  guint                       id,
                                                                  GtkCssSection              *section,
                                                                  GtkCssValue                *value);
+void                    _gtk_css_lookup_set_custom              (GtkCssLookup               *lookup,
+                                                                 int                         id,
+                                                                 GtkCssVariableValue        *value);
 
 static inline const GtkBitmask *
 _gtk_css_lookup_get_set_values (const GtkCssLookup *lookup)

gtk/gtkcssnode.c

@@ -445,9 +445,12 @@ gtk_css_node_real_update_style (GtkCssNode                   *cssnode,
     }
   else if (static_style != style && (change & GTK_CSS_CHANGE_TIMESTAMP))
     {
+      GtkCssNode *parent = gtk_css_node_get_parent (cssnode);
       new_style = gtk_css_animated_style_new_advance (GTK_CSS_ANIMATED_STYLE (style),
                                                       static_style,
-                                                      timestamp);
+                                                      parent ? gtk_css_node_get_style (parent) : NULL,
+                                                      timestamp,
+                                                      gtk_css_node_get_style_provider (cssnode));
     }
   else
     {

gtk/gtkcssnumbervalue.c

@@ -108,11 +108,12 @@ get_base_font_size_px (guint             property_id,
 }
 
 static GtkCssValue *
-gtk_css_value_number_compute (GtkCssValue      *number,
-                              guint             property_id,
-                              GtkStyleProvider *provider,
-                              GtkCssStyle      *style,
-                              GtkCssStyle      *parent_style)
+gtk_css_value_number_compute (GtkCssValue       *number,
+                              guint              property_id,
+                              GtkStyleProvider  *provider,
+                              GtkCssStyle       *style,
+                              GtkCssStyle       *parent_style,
+                              GtkCssVariableSet *variables)
 {
   double value;
 
@@ -130,7 +131,8 @@ gtk_css_value_number_compute (GtkCssValue      *number,
         {
           GtkCssValue *computed = _gtk_css_value_compute (number->calc.terms[i],
                                                           property_id, provider, style,
-                                                          parent_style);
+                                                          parent_style,
+                                                          variables);
           changed |= computed != number->calc.terms[i];
           new_values[i] = computed;
         }
@@ -337,6 +339,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_NUMBER = {
   gtk_css_value_number_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_number_print
 };
 

gtk/gtkcsspalettevalue.c

@@ -103,11 +103,12 @@ gtk_css_value_palette_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_palette_compute (GtkCssValue      *specified,
-                               guint             property_id,
-                               GtkStyleProvider *provider,
-                               GtkCssStyle      *style,
-                               GtkCssStyle      *parent_style)
+gtk_css_value_palette_compute (GtkCssValue       *specified,
+                               guint              property_id,
+                               GtkStyleProvider  *provider,
+                               GtkCssStyle       *style,
+                               GtkCssStyle       *parent_style,
+                               GtkCssVariableSet *variables)
 {
   GtkCssValue *computed_color;
   GtkCssValue *result;
@@ -120,7 +121,7 @@ gtk_css_value_palette_compute (GtkCssValue      *specified,
     {
       GtkCssValue *value = specified->color_values[i];
 
-      computed_color = _gtk_css_value_compute (value, property_id, provider, style, parent_style);
+      computed_color = _gtk_css_value_compute (value, property_id, provider, style, parent_style, variables);
       result->color_names[i] = g_strdup (specified->color_names[i]);
       result->color_values[i] = computed_color;
 
@@ -249,6 +250,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_PALETTE = {
   gtk_css_value_palette_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_palette_print
 };
 

gtk/gtkcsspositionvalue.c

@@ -36,16 +36,17 @@ gtk_css_value_position_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_position_compute (GtkCssValue      *position,
-                                guint             property_id,
-                                GtkStyleProvider *provider,
-                                GtkCssStyle      *style,
-                                GtkCssStyle      *parent_style)
+gtk_css_value_position_compute (GtkCssValue       *position,
+                                guint              property_id,
+                                GtkStyleProvider  *provider,
+                                GtkCssStyle       *style,
+                                GtkCssStyle       *parent_style,
+                                GtkCssVariableSet *variables)
 {
   GtkCssValue *x, *y;
 
-  x = _gtk_css_value_compute (position->x, property_id, provider, style, parent_style);
-  y = _gtk_css_value_compute (position->y, property_id, provider, style, parent_style);
+  x = _gtk_css_value_compute (position->x, property_id, provider, style, parent_style, variables);
+  y = _gtk_css_value_compute (position->y, property_id, provider, style, parent_style, variables);
   if (x == position->x && y == position->y)
     {
       _gtk_css_value_unref (x);
@@ -156,6 +157,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_POSITION = {
   gtk_css_value_position_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_position_print
 };
 

gtk/gtkcssprovider.c

@@ -22,10 +22,13 @@
 #include <gtk/css/gtkcss.h>
 #include "gtk/css/gtkcsstokenizerprivate.h"
 #include "gtk/css/gtkcssparserprivate.h"
+#include "gtk/css/gtkcssvariablevalueprivate.h"
 #include "gtkbitmaskprivate.h"
 #include "gtkcssarrayvalueprivate.h"
 #include "gtkcsscolorvalueprivate.h"
+#include "gtkcsscustompropertypoolprivate.h"
 #include "gtkcsskeyframesprivate.h"
+#include "gtkcssreferencevalueprivate.h"
 #include "gtkcssselectorprivate.h"
 #include "gtkcssshorthandpropertyprivate.h"
 #include "gtksettingsprivate.h"
@@ -113,6 +116,7 @@ struct GtkCssRuleset
   PropertyValue *styles;
   guint n_styles;
   guint owns_styles : 1;
+  GHashTable *custom_properties;
 };
 
 struct _GtkCssScanner
@@ -270,6 +274,8 @@ gtk_css_ruleset_clear (GtkCssRuleset *ruleset)
 	    gtk_css_section_unref (ruleset->styles[i].section);
         }
       g_free (ruleset->styles);
+      if (ruleset->custom_properties)
+        g_hash_table_unref (ruleset->custom_properties);
     }
   if (ruleset->selector)
     _gtk_css_selector_free (ruleset->selector);
@@ -285,7 +291,7 @@ gtk_css_ruleset_add (GtkCssRuleset       *ruleset,
 {
   guint i;
 
-  g_return_if_fail (ruleset->owns_styles || ruleset->n_styles == 0);
+  g_return_if_fail (ruleset->owns_styles || (ruleset->n_styles == 0 && ruleset->custom_properties == NULL));
 
   ruleset->owns_styles = TRUE;
 
@@ -315,6 +321,39 @@ gtk_css_ruleset_add (GtkCssRuleset       *ruleset,
     ruleset->styles[i].section = NULL;
 }
 
+static void
+unref_custom_property_name (gpointer pointer)
+{
+  GtkCssCustomPropertyPool *pool = gtk_css_custom_property_pool_get ();
+
+  gtk_css_custom_property_pool_unref (pool, GPOINTER_TO_INT (pointer));
+}
+
+static void
+gtk_css_ruleset_add_custom (GtkCssRuleset       *ruleset,
+                            const char          *name,
+                            GtkCssVariableValue *value)
+{
+  GtkCssCustomPropertyPool *pool;
+  int id;
+
+  g_return_if_fail (ruleset->owns_styles || (ruleset->n_styles == 0 && ruleset->custom_properties == NULL));
+
+  ruleset->owns_styles = TRUE;
+
+  if (ruleset->custom_properties == NULL)
+    {
+      ruleset->custom_properties = g_hash_table_new_full (g_direct_hash, g_direct_equal,
+                                                          unref_custom_property_name,
+                                                          (GDestroyNotify) gtk_css_variable_value_unref);
+    }
+
+  pool = gtk_css_custom_property_pool_get ();
+  id = gtk_css_custom_property_pool_add (pool, name);
+
+  g_hash_table_replace (ruleset->custom_properties, GINT_TO_POINTER (id), value);
+}
+
 static void
 gtk_css_scanner_destroy (GtkCssScanner *scanner)
 {
@@ -490,7 +529,7 @@ gtk_css_style_provider_lookup (GtkStyleProvider             *provider,
         {
           ruleset = gtk_css_selector_matches_get (&tree_rules, i);
 
-          if (ruleset->styles == NULL)
+          if (ruleset->styles == NULL && ruleset->custom_properties == NULL)
             continue;
 
           for (j = 0; j < ruleset->n_styles; j++)
@@ -506,6 +545,18 @@ gtk_css_style_provider_lookup (GtkStyleProvider             *provider,
                                    ruleset->styles[j].section,
                                    ruleset->styles[j].value);
             }
+
+          if (ruleset->custom_properties)
+            {
+              GHashTableIter iter;
+              gpointer id;
+              GtkCssVariableValue *value;
+
+              g_hash_table_iter_init (&iter, ruleset->custom_properties);
+
+              while (g_hash_table_iter_next (&iter, &id, (gpointer) &value))
+                _gtk_css_lookup_set_custom (lookup, GPOINTER_TO_INT (id), value);
+            }
         }
     }
   gtk_css_selector_matches_clear (&tree_rules);
@@ -572,7 +623,7 @@ css_provider_commit (GtkCssProvider  *css_provider,
   GtkCssProviderPrivate *priv = gtk_css_provider_get_instance_private (css_provider);
   guint i;
 
-  if (ruleset->styles == NULL)
+  if (ruleset->styles == NULL && ruleset->custom_properties == NULL)
     {
       for (i = 0; i < gtk_css_selectors_get_size (selectors); i++)
         _gtk_css_selector_free (gtk_css_selectors_get (selectors, i));
@@ -814,6 +865,42 @@ parse_declaration (GtkCssScanner *scanner,
   if (name == NULL)
     goto out;
 
+  /* This is a custom property */
+  if (name[0] == '-' && name[1] == '-')
+    {
+      GtkCssVariableValue *value;
+      GtkCssSection *section;
+
+      if (!gtk_css_parser_try_token (scanner->parser, GTK_CSS_TOKEN_COLON))
+        {
+          gtk_css_parser_error_syntax (scanner->parser, "Expected ':'");
+          goto out;
+        }
+
+      value = gtk_css_parser_parse_value_into_token_stream (scanner->parser);
+      if (value == NULL)
+        goto out;
+
+      if (gtk_keep_css_sections)
+        {
+          section = gtk_css_section_new (gtk_css_parser_get_file (scanner->parser),
+                                         gtk_css_parser_get_block_location (scanner->parser),
+                                         gtk_css_parser_get_end_location (scanner->parser));
+        }
+      else
+        section = NULL;
+
+      if (section != NULL)
+        {
+          gtk_css_variable_value_set_section (value, section);
+          gtk_css_section_unref (section);
+        }
+
+      gtk_css_ruleset_add_custom (ruleset, name, value);
+
+      goto out;
+    }
+
   property = _gtk_style_property_lookup (name);
 
   if (property)
@@ -827,15 +914,60 @@ parse_declaration (GtkCssScanner *scanner,
           goto out;
         }
 
-      value = _gtk_style_property_parse_value (property, scanner->parser);
-
-      if (value == NULL)
-        goto out;
-
-      if (!gtk_css_parser_has_token (scanner->parser, GTK_CSS_TOKEN_EOF))
+      if (gtk_css_parser_has_references (scanner->parser))
         {
-          gtk_css_parser_error_syntax (scanner->parser, "Junk at end of value for %s", property->name);
-          goto out;
+          GtkCssVariableValue *var_value;
+
+          var_value = gtk_css_parser_parse_value_into_token_stream (scanner->parser);
+          if (var_value == NULL)
+            goto out;
+
+          if (GTK_IS_CSS_SHORTHAND_PROPERTY (property))
+            {
+              GtkCssShorthandProperty *shorthand = GTK_CSS_SHORTHAND_PROPERTY (property);
+              guint i, n;
+              GtkCssValue **values;
+
+              n = _gtk_css_shorthand_property_get_n_subproperties (shorthand);
+
+              values = g_new (GtkCssValue *, n);
+
+              for (i = 0; i < n; i++)
+                {
+                  GtkCssValue *child =
+                    _gtk_css_reference_value_new (property,
+                                                  var_value,
+                                                  gtk_css_parser_get_file (scanner->parser));
+                  _gtk_css_reference_value_set_subproperty (child, i);
+
+                  values[i] = _gtk_css_array_value_get_nth (child, i);
+                }
+
+              value = _gtk_css_array_value_new_from_array (values, n);
+              g_free (values);
+            }
+          else
+            {
+              value = _gtk_css_reference_value_new (property,
+                                                    var_value,
+                                                    gtk_css_parser_get_file (scanner->parser));
+            }
+
+          gtk_css_variable_value_unref (var_value);
+        }
+      else
+        {
+          value = _gtk_style_property_parse_value (property, scanner->parser);
+
+          if (value == NULL)
+            goto out;
+
+          if (!gtk_css_parser_has_token (scanner->parser, GTK_CSS_TOKEN_EOF))
+            {
+              gtk_css_parser_error_syntax (scanner->parser, "Junk at end of value for %s", property->name);
+              gtk_css_value_unref (value);
+              goto out;
+            }
         }
 
       if (gtk_keep_css_sections)
@@ -1112,7 +1244,7 @@ gtk_css_provider_load_from_data (GtkCssProvider  *css_provider,
   if (length < 0)
     length = strlen (data);
 
-  bytes = g_bytes_new_static (data, length);
+  bytes = g_bytes_new (data, length);
 
   gtk_css_provider_load_from_bytes (css_provider, bytes);
 
@@ -1139,7 +1271,7 @@ gtk_css_provider_load_from_string (GtkCssProvider *css_provider,
   g_return_if_fail (GTK_IS_CSS_PROVIDER (css_provider));
   g_return_if_fail (string != NULL);
 
-  bytes = g_bytes_new_static (string, strlen (string));
+  bytes = g_bytes_new (string, strlen (string));
 
   gtk_css_provider_load_from_bytes (css_provider, bytes);
 
@@ -1473,6 +1605,20 @@ compare_properties (gconstpointer a, gconstpointer b, gpointer style)
                  _gtk_style_property_get_name (GTK_STYLE_PROPERTY (styles[*ub].property)));
 }
 
+static int
+compare_custom_properties (gconstpointer a, gconstpointer b, gpointer user_data)
+{
+  GtkCssCustomPropertyPool *pool = user_data;
+  int id1 = GPOINTER_TO_INT (*((gconstpointer *) a));
+  int id2 = GPOINTER_TO_INT (*((gconstpointer *) b));
+  const char *name1, *name2;
+
+  name1 = gtk_css_custom_property_pool_get_name (pool, id1);
+  name2 = gtk_css_custom_property_pool_get_name (pool, id2);
+
+  return strcmp (name1, name2);
+}
+
 static void
 gtk_css_ruleset_print (const GtkCssRuleset *ruleset,
                        GString             *str)
@@ -1503,6 +1649,31 @@ gtk_css_ruleset_print (const GtkCssRuleset *ruleset,
           g_string_append (str, ";\n");
         }
 
+        if (ruleset->custom_properties)
+          {
+            GtkCssCustomPropertyPool *pool = gtk_css_custom_property_pool_get ();
+            GPtrArray *keys;
+
+            keys = g_hash_table_get_keys_as_ptr_array (ruleset->custom_properties);
+            g_ptr_array_sort_with_data (keys, compare_custom_properties, pool);
+
+            for (i = 0; i < keys->len; i++)
+              {
+                int id = GPOINTER_TO_INT (g_ptr_array_index (keys, i));
+                const char *name = gtk_css_custom_property_pool_get_name (pool, id);
+                GtkCssVariableValue *value = g_hash_table_lookup (ruleset->custom_properties,
+                                                                  GINT_TO_POINTER (id));
+
+                g_string_append (str, "  ");
+                g_string_append (str, name);
+                g_string_append (str, ": ");
+                gtk_css_variable_value_print (value, str);
+                g_string_append (str, ";\n");
+              }
+
+            g_ptr_array_unref (keys);
+          }
+
       g_free (sorted);
     }
 

gtk/gtkcssreferencevalue.c

@@ -0,0 +1,275 @@
+/*
+ * Copyright (C) 2023 GNOME Foundation Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Alice Mikhaylenko <alicem@gnome.org>
+ */
+
+#include "config.h"
+
+#include "gtkcssreferencevalueprivate.h"
+
+#include "gtkcssarrayvalueprivate.h"
+#include "gtkcsscustompropertypoolprivate.h"
+#include "gtkcssshorthandpropertyprivate.h"
+#include "gtkcssstyleprivate.h"
+#include "gtkcssunsetvalueprivate.h"
+#include "gtkcssvalueprivate.h"
+#include "gtkstyleproviderprivate.h"
+
+#define MAX_TOKEN_LENGTH 65536
+
+struct _GtkCssValue {
+  GTK_CSS_VALUE_BASE
+
+  GtkStyleProperty *property;
+  GtkCssVariableValue *value;
+  GFile *file;
+  guint subproperty;
+};
+
+static void
+gtk_css_value_reference_free (GtkCssValue *value)
+{
+  gtk_css_variable_value_unref (value->value);
+  if (value->file)
+    g_object_unref (value->file);
+}
+
+static gboolean
+resolve_references_do (GtkCssVariableValue *value,
+                       GtkCssVariableSet   *style_variables,
+                       GtkCssVariableSet   *keyframes_variables,
+                       gboolean             root,
+                       GPtrArray           *refs,
+                       gsize               *out_length,
+                       gsize               *out_n_refs)
+{
+  GtkCssCustomPropertyPool *pool = gtk_css_custom_property_pool_get ();
+  gsize i;
+  gsize length = value->length;
+  gsize n_refs = 0;
+
+  if (value->is_invalid)
+    goto error;
+
+  if (!root)
+    {
+      n_refs += 1;
+      g_ptr_array_add (refs, value);
+    }
+
+  for (i = 0; i < value->n_references; i++)
+    {
+      GtkCssVariableValueReference *ref = &value->references[i];
+      int id = gtk_css_custom_property_pool_lookup (pool, ref->name);
+      GtkCssVariableValue *var_value = NULL;
+      gsize var_length, var_refs;
+      GtkCssVariableSet *source = style_variables;
+
+      if (keyframes_variables)
+        var_value = gtk_css_variable_set_lookup (keyframes_variables, id, NULL);
+
+      if (!var_value && style_variables)
+        var_value = gtk_css_variable_set_lookup (style_variables, id, &source);
+
+      if (!var_value || !resolve_references_do (var_value, source, keyframes_variables,
+                                                FALSE, refs, &var_length, &var_refs))
+        {
+          var_value = ref->fallback;
+
+          if (!var_value || !resolve_references_do (var_value, style_variables, keyframes_variables,
+                                                    FALSE, refs, &var_length, &var_refs))
+            goto error;
+        }
+
+      length += var_length - ref->length;
+      n_refs += var_refs;
+
+      if (length > MAX_TOKEN_LENGTH)
+        goto error;
+    }
+
+  if (out_length)
+    *out_length = length;
+
+  if (out_n_refs)
+    *out_n_refs = n_refs;
+
+  return TRUE;
+
+error:
+  /* Remove the references we added as if nothing happened */
+  g_ptr_array_remove_range (refs, refs->len - n_refs, n_refs);
+
+  if (out_length)
+    *out_length = 0;
+
+  if (out_n_refs)
+    *out_n_refs = 0;
+
+  return FALSE;
+}
+
+static GtkCssVariableValue **
+resolve_references (GtkCssVariableValue *input,
+                    GtkCssStyle         *style,
+                    GtkCssVariableSet   *keyframes_variables,
+                    gsize               *n_refs)
+{
+  GPtrArray *refs = g_ptr_array_new ();
+
+  if (!resolve_references_do (input, style->variables, keyframes_variables, TRUE, refs, NULL, NULL))
+    return NULL;
+
+  return (GtkCssVariableValue **) g_ptr_array_steal (refs, n_refs);
+}
+
+static void
+parser_error (GtkCssParser         *parser,
+              const GtkCssLocation *start,
+              const GtkCssLocation *end,
+              const GError         *error,
+              gpointer              user_data)
+{
+  GtkStyleProvider *provider = user_data;
+  GtkCssSection *section;
+
+  section = gtk_css_section_new (gtk_css_parser_get_file (parser),
+                                 start,
+                                 end);
+
+  gtk_style_provider_emit_error (provider, section, (GError *) error);
+
+  gtk_css_section_unref (section);
+}
+
+static GtkCssValue *
+gtk_css_value_reference_compute (GtkCssValue       *value,
+                                 guint              property_id,
+                                 GtkStyleProvider  *provider,
+                                 GtkCssStyle       *style,
+                                 GtkCssStyle       *parent_style,
+                                 GtkCssVariableSet *variables)
+{
+  GtkCssValue *result = NULL, *computed;
+  GtkCssVariableValue **refs;
+  gsize n_refs = 0;
+
+  refs = resolve_references (value->value, style, variables, &n_refs);
+
+  if (refs != NULL)
+    {
+      GtkCssParser *value_parser =
+        gtk_css_parser_new_for_token_stream (value->value,
+                                             value->file,
+                                             refs,
+                                             n_refs,
+                                             parser_error, provider, NULL);
+
+      result = _gtk_style_property_parse_value (value->property, value_parser);
+      gtk_css_parser_unref (value_parser);
+    }
+
+  if (result == NULL)
+    result = _gtk_css_unset_value_new ();
+
+  if (GTK_IS_CSS_SHORTHAND_PROPERTY (value->property))
+    {
+      GtkCssValue *sub = gtk_css_value_ref (_gtk_css_array_value_get_nth (result, value->subproperty));
+      gtk_css_value_unref (result);
+      result = sub;
+    }
+
+  computed = _gtk_css_value_compute (result,
+                                     property_id,
+                                     provider,
+                                     style,
+                                     parent_style,
+                                     variables);
+
+  gtk_css_value_unref (result);
+
+  return computed;
+}
+
+static gboolean
+gtk_css_value_reference_equal (const GtkCssValue *value1,
+                               const GtkCssValue *value2)
+{
+  return FALSE;
+}
+
+static GtkCssValue *
+gtk_css_value_reference_transition (GtkCssValue *start,
+                                    GtkCssValue *end,
+                                    guint        property_id,
+                                    double       progress)
+{
+  return NULL;
+}
+
+static gboolean
+gtk_css_value_reference_contains_variables (const GtkCssValue *value)
+{
+  return TRUE;
+}
+
+static void
+gtk_css_value_reference_print (const GtkCssValue *value,
+                               GString           *string)
+{
+  gtk_css_variable_value_print (value->value, string);
+}
+
+static const GtkCssValueClass GTK_CSS_VALUE_REFERENCE = {
+  "GtkCssReferenceValue",
+  gtk_css_value_reference_free,
+  gtk_css_value_reference_compute,
+  gtk_css_value_reference_equal,
+  gtk_css_value_reference_transition,
+  NULL,
+  NULL,
+  gtk_css_value_reference_contains_variables,
+  gtk_css_value_reference_print
+};
+
+GtkCssValue *
+_gtk_css_reference_value_new (GtkStyleProperty    *property,
+                              GtkCssVariableValue *value,
+                              GFile               *file)
+{
+  GtkCssValue *result;
+
+  result = _gtk_css_value_new (GtkCssValue, &GTK_CSS_VALUE_REFERENCE);
+  result->property = property;
+  result->value = gtk_css_variable_value_ref (value);
+
+  if (file)
+    result->file = g_object_ref (file);
+  else
+    result->file = NULL;
+
+  return result;
+}
+
+void
+_gtk_css_reference_value_set_subproperty (GtkCssValue *value,
+                                          guint        property)
+{
+  g_assert (GTK_IS_CSS_SHORTHAND_PROPERTY (value->property));
+
+  value->subproperty = property;
+}

gtk/gtkcssreferencevalueprivate.h

@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2023 GNOME Foundation Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Alice Mikhaylenko <alicem@gnome.org>
+ */
+
+#pragma once
+
+#include <gtk/css/gtkcss.h>
+#include "gtkcssvalueprivate.h"
+#include "gtkstylepropertyprivate.h"
+#include "css/gtkcssvariablevalueprivate.h"
+
+G_BEGIN_DECLS
+
+GtkCssValue *_gtk_css_reference_value_new             (GtkStyleProperty    *property,
+                                                       GtkCssVariableValue *value,
+                                                       GFile               *file);
+void         _gtk_css_reference_value_set_subproperty (GtkCssValue         *value,
+                                                       guint                property);
+
+G_END_DECLS

gtk/gtkcssrepeatvalue.c

@@ -34,11 +34,12 @@ gtk_css_value_repeat_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_repeat_compute (GtkCssValue      *value,
-                              guint             property_id,
-                              GtkStyleProvider *provider,
-                              GtkCssStyle      *style,
-                              GtkCssStyle      *parent_style)
+gtk_css_value_repeat_compute (GtkCssValue       *value,
+                              guint              property_id,
+                              GtkStyleProvider  *provider,
+                              GtkCssStyle       *style,
+                              GtkCssStyle       *parent_style,
+                              GtkCssVariableSet *variables)
 {
   return _gtk_css_value_ref (value);
 }
@@ -120,6 +121,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_BACKGROUND_REPEAT = {
   gtk_css_value_repeat_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_background_repeat_print
 };
 
@@ -131,6 +133,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_BORDER_REPEAT = {
   gtk_css_value_repeat_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_border_repeat_print
 };
 /* BACKGROUND REPEAT */

gtk/gtkcssselector.c

@@ -892,6 +892,48 @@ DEFINE_SIMPLE_SELECTOR(pseudoclass_position, PSEUDOCLASS_POSITION, print_pseudoc
                        match_pseudoclass_position, hash_pseudoclass_position, comp_pseudoclass_position,
                        FALSE, TRUE, FALSE, TRUE)
 #undef GTK_CSS_CHANGE_PSEUDOCLASS_POSITION
+
+/* PSEUDOCLASS FOR ROOT */
+
+static void
+print_pseudoclass_root (const GtkCssSelector *selector,
+                        GString              *string)
+{
+  g_string_append (string, ":root");
+}
+
+static gboolean
+match_pseudoclass_root (const GtkCssSelector *selector,
+                        GtkCssNode           *node)
+{
+  return gtk_css_node_get_parent (node) == NULL;
+}
+
+static guint
+hash_pseudoclass_root (const GtkCssSelector *selector)
+{
+  return GPOINTER_TO_UINT (selector->class);
+}
+
+static int
+comp_pseudoclass_root (const GtkCssSelector *a,
+                       const GtkCssSelector *b)
+{
+  return 0;
+}
+
+static GtkCssChange
+change_pseudoclass_root (const GtkCssSelector *selector)
+{
+  return 0;
+}
+
+#define GTK_CSS_CHANGE_PSEUDOCLASS_ROOT change_pseudoclass_root(selector)
+DEFINE_SIMPLE_SELECTOR(pseudoclass_root, PSEUDOCLASS_ROOT, print_pseudoclass_root,
+                       match_pseudoclass_root, hash_pseudoclass_root, comp_pseudoclass_root,
+                       FALSE, TRUE, FALSE, TRUE)
+#undef GTK_CSS_CHANGE_PSEUDOCLASS_ROOT
+
 /* API */
 
 static guint
@@ -1267,6 +1309,7 @@ gtk_css_selector_parse_selector_pseudo_class (GtkCssParser   *parser,
         PositionType   position_type;
         int            position_a;
         int            position_b;
+        gboolean       is_root;
       } pseudo_classes[] = {
         { "first-child",    0,                           POSITION_FORWARD,  0, 1 },
         { "last-child",     0,                           POSITION_BACKWARD, 0, 1 },
@@ -1283,6 +1326,7 @@ gtk_css_selector_parse_selector_pseudo_class (GtkCssParser   *parser,
         { "checked",        GTK_STATE_FLAG_CHECKED, },
         { "focus-visible",  GTK_STATE_FLAG_FOCUS_VISIBLE, },
         { "focus-within",   GTK_STATE_FLAG_FOCUS_WITHIN, },
+        { "root",           0,                           0,                 0, 0, TRUE },
       };
       guint i;
 
@@ -1297,6 +1341,12 @@ gtk_css_selector_parse_selector_pseudo_class (GtkCssParser   *parser,
                                                    selector);
                   selector->state.state = pseudo_classes[i].state_flag;
                 }
+              else if (pseudo_classes[i].is_root)
+                {
+                  selector = gtk_css_selector_new (negate ? &GTK_CSS_SELECTOR_NOT_PSEUDOCLASS_ROOT
+                                                          : &GTK_CSS_SELECTOR_PSEUDOCLASS_ROOT,
+                                                   selector);
+                }
               else
                 {
                   selector = gtk_css_selector_new (negate ? &GTK_CSS_SELECTOR_NOT_PSEUDOCLASS_POSITION

gtk/gtkcssshadowvalue.c

@@ -112,11 +112,12 @@ gtk_css_value_shadow_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_shadow_compute (GtkCssValue      *value,
-                              guint             property_id,
-                              GtkStyleProvider *provider,
-                              GtkCssStyle      *style,
-                              GtkCssStyle      *parent_style)
+gtk_css_value_shadow_compute (GtkCssValue       *value,
+                              guint              property_id,
+                              GtkStyleProvider  *provider,
+                              GtkCssStyle       *style,
+                              GtkCssStyle       *parent_style,
+                              GtkCssVariableSet *variables)
 {
   guint i;
   ShadowValue *shadows;
@@ -127,11 +128,11 @@ gtk_css_value_shadow_compute (GtkCssValue      *value,
     {
       const ShadowValue *shadow = &value->shadows[i];
 
-      shadows[i].hoffset = _gtk_css_value_compute (shadow->hoffset, property_id, provider, style, parent_style);
-      shadows[i].voffset = _gtk_css_value_compute (shadow->voffset, property_id, provider, style, parent_style);
-      shadows[i].radius = _gtk_css_value_compute (shadow->radius, property_id, provider, style, parent_style);
-      shadows[i].spread = _gtk_css_value_compute (shadow->spread, property_id, provider, style, parent_style),
-      shadows[i].color = _gtk_css_value_compute (shadow->color, property_id, provider, style, parent_style);
+      shadows[i].hoffset = _gtk_css_value_compute (shadow->hoffset, property_id, provider, style, parent_style, variables);
+      shadows[i].voffset = _gtk_css_value_compute (shadow->voffset, property_id, provider, style, parent_style, variables);
+      shadows[i].radius = _gtk_css_value_compute (shadow->radius, property_id, provider, style, parent_style, variables);
+      shadows[i].spread = _gtk_css_value_compute (shadow->spread, property_id, provider, style, parent_style, variables),
+      shadows[i].color = _gtk_css_value_compute (shadow->color, property_id, provider, style, parent_style, variables);
       shadows[i].inset = shadow->inset;
     }
 
@@ -283,6 +284,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_SHADOW = {
   gtk_css_value_shadow_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_shadow_print
 };
 

gtk/gtkcssstaticstyle.c

@@ -322,6 +322,12 @@ gtk_css_static_style_dispose (GObject *object)
       style->sections = NULL;
     }
 
+  if (style->original_values)
+    {
+      g_ptr_array_unref (style->original_values);
+      style->original_values = NULL;
+    }
+
   G_OBJECT_CLASS (gtk_css_static_style_parent_class)->dispose (object);
 }
 
@@ -331,6 +337,19 @@ gtk_css_static_style_get_static_style (GtkCssStyle *style)
   return (GtkCssStaticStyle *)style;
 }
 
+static GtkCssValue *
+gtk_css_static_style_get_original_value (GtkCssStyle *style,
+                                         guint        id)
+{
+  GtkCssStaticStyle *sstyle = GTK_CSS_STATIC_STYLE (style);
+
+  if (sstyle->original_values == NULL ||
+      id >= sstyle->original_values->len)
+    return NULL;
+
+  return g_ptr_array_index (sstyle->original_values, id);
+}
+
 static void
 gtk_css_static_style_class_init (GtkCssStaticStyleClass *klass)
 {
@@ -341,6 +360,7 @@ gtk_css_static_style_class_init (GtkCssStaticStyleClass *klass)
 
   style_class->get_section = gtk_css_static_style_get_section;
   style_class->get_static_style = gtk_css_static_style_get_static_style;
+  style_class->get_original_value = gtk_css_static_style_get_original_value;
 
   gtk_css_core_values_init ();
   gtk_css_background_values_init ();
@@ -369,6 +389,13 @@ maybe_unref_section (gpointer section)
     gtk_css_section_unref (section);
 }
 
+static void
+maybe_unref_value (gpointer value)
+{
+  if (value)
+    _gtk_css_value_unref (value);
+}
+
 static inline void
 gtk_css_take_value (GtkCssValue **variable,
                     GtkCssValue  *value)
@@ -382,6 +409,7 @@ static void
 gtk_css_static_style_set_value (GtkCssStaticStyle *sstyle,
                                 guint              id,
                                 GtkCssValue       *value,
+                                GtkCssValue       *original_value,
                                 GtkCssSection     *section)
 {
   GtkCssStyle *style = (GtkCssStyle *)sstyle;
@@ -684,6 +712,22 @@ gtk_css_static_style_set_value (GtkCssStaticStyle *sstyle,
         g_ptr_array_set_size (sstyle->sections, id + 1);
       g_ptr_array_index (sstyle->sections, id) = gtk_css_section_ref (section);
     }
+
+  if (sstyle->original_values && sstyle->original_values->len > id &&
+      g_ptr_array_index (sstyle->original_values, id))
+    {
+      _gtk_css_value_unref (g_ptr_array_index (sstyle->original_values, id));
+      g_ptr_array_index (sstyle->original_values, id) = NULL;
+    }
+
+  if (original_value)
+    {
+      if (sstyle->original_values == NULL)
+        sstyle->original_values = g_ptr_array_new_with_free_func (maybe_unref_value);
+      if (sstyle->original_values->len <= id)
+        g_ptr_array_set_size (sstyle->original_values, id + 1);
+      g_ptr_array_index (sstyle->original_values, id) = _gtk_css_value_ref (original_value);
+    }
 }
 
 static GtkCssStyle *default_style;
@@ -912,6 +956,35 @@ gtk_css_lookup_resolve (GtkCssLookup      *lookup,
   gtk_internal_return_if_fail (GTK_IS_CSS_STATIC_STYLE (style));
   gtk_internal_return_if_fail (parent_style == NULL || GTK_IS_CSS_STYLE (parent_style));
 
+  if (lookup->custom_values)
+    {
+      GHashTableIter iter;
+      gpointer id;
+      GtkCssVariableValue *value;
+
+      style->variables = gtk_css_variable_set_new ();
+
+      g_hash_table_iter_init (&iter, lookup->custom_values);
+
+      while (g_hash_table_iter_next (&iter, &id, (gpointer) &value))
+        gtk_css_variable_set_add (style->variables, GPOINTER_TO_INT (id), value);
+
+      gtk_css_variable_set_resolve_cycles (style->variables);
+
+      if (parent_style)
+        {
+          GtkCssStyle *parent_sstyle = GTK_CSS_STYLE (parent_style);
+          gtk_css_variable_set_set_parent (style->variables,
+                                           parent_sstyle->variables);
+        }
+    }
+  else if (parent_style)
+    {
+      GtkCssStyle *parent_sstyle = GTK_CSS_STYLE (parent_style);
+      if (parent_sstyle->variables)
+        style->variables = gtk_css_variable_set_ref (parent_sstyle->variables);
+    }
+
   if (_gtk_bitmask_is_empty (_gtk_css_lookup_get_set_values (lookup)))
     {
       style->background = (GtkCssBackgroundValues *)gtk_css_values_ref (gtk_css_background_initial_values);
@@ -1047,7 +1120,7 @@ gtk_css_static_style_compute_value (GtkCssStaticStyle *style,
                                     GtkCssValue       *specified,
                                     GtkCssSection     *section)
 {
-  GtkCssValue *value;
+  GtkCssValue *value, *original_value;
   GtkBorderStyle border_style;
 
   gtk_internal_return_if_fail (id < GTK_CSS_PROPERTY_N_PROPERTIES);
@@ -1068,7 +1141,7 @@ gtk_css_static_style_compute_value (GtkCssStaticStyle *style,
         border_style = _gtk_css_border_style_value_get (gtk_css_style_get_value ((GtkCssStyle *)style, id - 1));
         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
           {
-            gtk_css_static_style_set_value (style, id, gtk_css_dimension_value_new (0, GTK_CSS_NUMBER), section);
+            gtk_css_static_style_set_value (style, id, gtk_css_dimension_value_new (0, GTK_CSS_NUMBER), NULL, section);
             return;
           }
         break;
@@ -1085,19 +1158,34 @@ gtk_css_static_style_compute_value (GtkCssStaticStyle *style,
    */
   if (specified)
     {
-      value = _gtk_css_value_compute (specified, id, provider, (GtkCssStyle *)style, parent_style);
+      value = _gtk_css_value_compute (specified, id, provider, (GtkCssStyle *)style, parent_style, NULL);
+
+      if (gtk_css_value_contains_variables (specified))
+        original_value = specified;
+      else
+        original_value = NULL;
     }
   else if (parent_style && _gtk_css_style_property_is_inherit (_gtk_css_style_property_lookup_by_id (id)))
     {
+      GtkCssValue *parent_original_value;
+
       /* Just take the style from the parent */
       value = _gtk_css_value_ref (gtk_css_style_get_value (parent_style, id));
+
+      parent_original_value = gtk_css_style_get_original_value (parent_style, id);
+
+      if (parent_original_value)
+        original_value = parent_original_value;
+      else
+        original_value = NULL;
     }
   else
     {
       value = _gtk_css_initial_value_new_compute (id, provider, (GtkCssStyle *)style, parent_style);
+      original_value = NULL;
     }
 
-  gtk_css_static_style_set_value (style, id, value, section);
+  gtk_css_static_style_set_value (style, id, value, original_value, section);
 }
 
 GtkCssChange
@@ -1107,3 +1195,15 @@ gtk_css_static_style_get_change (GtkCssStaticStyle *style)
 
   return style->change;
 }
+
+void
+gtk_css_custom_values_compute_changes_and_affects (GtkCssStyle    *style1,
+                                                   GtkCssStyle    *style2,
+                                                   GtkBitmask    **changes,
+                                                   GtkCssAffects  *affects)
+{
+  if (gtk_css_variable_set_equal (style1->variables, style2->variables))
+    return;
+
+  *changes = _gtk_bitmask_set (*changes, GTK_CSS_PROPERTY_CUSTOM, TRUE);
+}

gtk/gtkcssstaticstyleprivate.h

@@ -40,6 +40,7 @@ struct _GtkCssStaticStyle
   GtkCssStyle parent;
 
   GPtrArray             *sections;             /* sections the values are defined in */
+  GPtrArray             *original_values;
 
   GtkCssChange           change;               /* change as returned by value lookup */
 };

gtk/gtkcssstringvalue.c

@@ -35,11 +35,12 @@ gtk_css_value_string_free (GtkCssValue *value)
 }
 
 static GtkCssValue *
-gtk_css_value_string_compute (GtkCssValue      *value,
-                              guint             property_id,
-                              GtkStyleProvider *provider,
-                              GtkCssStyle      *style,
-                              GtkCssStyle      *parent_style)
+gtk_css_value_string_compute (GtkCssValue       *value,
+                              guint              property_id,
+                              GtkStyleProvider  *provider,
+                              GtkCssStyle       *style,
+                              GtkCssStyle       *parent_style,
+                              GtkCssVariableSet *variables)
 {
   return _gtk_css_value_ref (value);
 }
@@ -125,6 +126,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_STRING = {
   gtk_css_value_string_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_string_print
 };
 
@@ -136,6 +138,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_IDENT = {
   gtk_css_value_string_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_ident_print
 };
 

gtk/gtkcssstyle.c

@@ -24,6 +24,7 @@
 
 #include "gtkcssanimationprivate.h"
 #include "gtkcssarrayvalueprivate.h"
+#include "gtkcsscustompropertypoolprivate.h"
 #include "gtkcssenumvalueprivate.h"
 #include "gtkcssinheritvalueprivate.h"
 #include "gtkcssinitialvalueprivate.h"
@@ -73,6 +74,9 @@ gtk_css_style_finalize (GObject *object)
   gtk_css_values_unref ((GtkCssValues *)style->size);
   gtk_css_values_unref ((GtkCssValues *)style->other);
 
+  if (style->variables)
+    gtk_css_variable_set_unref (style->variables);
+
   G_OBJECT_CLASS (gtk_css_style_parent_class)->finalize (object);
 }
 
@@ -311,6 +315,15 @@ gtk_css_style_get_static_style (GtkCssStyle *style)
   return GTK_CSS_STYLE_GET_CLASS (style)->get_static_style (style);
 }
 
+GtkCssValue *
+gtk_css_style_get_original_value (GtkCssStyle *style,
+                                  guint        id)
+{
+  gtk_internal_return_val_if_fail (GTK_IS_CSS_STYLE (style), NULL);
+
+  return GTK_CSS_STYLE_GET_CLASS (style)->get_original_value (style, id);
+}
+
 /*
  * gtk_css_style_print:
  * @style: a `GtkCssStyle`
@@ -368,6 +381,34 @@ gtk_css_style_print (GtkCssStyle *style,
       retval = TRUE;
     }
 
+    if (style->variables)
+      {
+        GtkCssCustomPropertyPool *pool = gtk_css_custom_property_pool_get ();
+        GArray *ids = gtk_css_variable_set_list_ids (style->variables);
+
+        for (i = 0; i < ids->len; i++)
+          {
+            int id = g_array_index (ids, int, i);
+            const char *name = gtk_css_custom_property_pool_get_name (pool, id);
+            GtkCssVariableValue *value = gtk_css_variable_set_lookup (style->variables, id, NULL);
+
+            g_string_append_printf (string, "%*s%s: ", indent, "", name);
+            gtk_css_variable_value_print (value, string);
+            g_string_append_c (string, ';');
+
+            if (value->section)
+              {
+                g_string_append (string, " /* ");
+                gtk_css_section_print (value->section, string);
+                g_string_append (string, " */");
+              }
+
+            g_string_append_c (string, '\n');
+          }
+
+        retval = TRUE;
+      }
+
   return retval;
 }
 
@@ -837,3 +878,13 @@ gtk_css_values_new (GtkCssValuesType type)
 
   return values;
 }
+
+GtkCssVariableValue *
+gtk_css_style_get_custom_property (GtkCssStyle *style,
+                                   int          id)
+{
+  if (style->variables)
+    return gtk_css_variable_set_lookup (style->variables, id, NULL);
+
+  return NULL;
+}

gtk/gtkcssstylechange.c

@@ -102,6 +102,12 @@ compute_change (GtkCssStyleChange *change)
                                                       change->new_style,
                                                       &change->changes,
                                                       &change->affects);
+
+  if (change->old_style->variables != change->new_style->variables)
+    gtk_css_custom_values_compute_changes_and_affects (change->old_style,
+                                                       change->new_style,
+                                                       &change->changes,
+                                                       &change->affects);
 }
 
 void

gtk/gtkcssstyleprivate.h

@@ -24,6 +24,8 @@
 
 #include "gtk/gtkbitmaskprivate.h"
 #include "gtk/gtkcssvalueprivate.h"
+#include "gtk/gtkcssvariablesetprivate.h"
+#include "gtk/css/gtkcssvariablevalueprivate.h"
 
 G_BEGIN_DECLS
 
@@ -232,6 +234,10 @@ struct _GtkCssStyle
   GtkCssTransitionValues  *transition;
   GtkCssSizeValues        *size;
   GtkCssOtherValues       *other;
+  GtkCssVariableSet       *variables;
+
+  GtkCssValue             *variable_values;
+  int                      n_variable_values;
 };
 
 struct _GtkCssStyleClass
@@ -246,6 +252,9 @@ struct _GtkCssStyleClass
   gboolean              (* is_static)                           (GtkCssStyle            *style);
 
   GtkCssStaticStyle *   (* get_static_style)                    (GtkCssStyle            *style);
+
+  GtkCssValue *         (* get_original_value)                  (GtkCssStyle            *style,
+                                                                 guint                   id);
 };
 
 GType                   gtk_css_style_get_type                  (void) G_GNUC_CONST;
@@ -257,6 +266,9 @@ GtkCssSection *         gtk_css_style_get_section               (GtkCssStyle
 gboolean                gtk_css_style_is_static                 (GtkCssStyle            *style) G_GNUC_PURE;
 GtkCssStaticStyle *     gtk_css_style_get_static_style          (GtkCssStyle            *style);
 
+GtkCssValue *           gtk_css_style_get_original_value        (GtkCssStyle            *style,
+                                                                 guint                   id) G_GNUC_PURE;
+
 char *                  gtk_css_style_to_string                 (GtkCssStyle            *style);
 gboolean                gtk_css_style_print                     (GtkCssStyle            *style,
                                                                  GString                *string,
@@ -268,6 +280,9 @@ char *                  gtk_css_style_compute_font_features     (GtkCssStyle
 PangoAttrList *         gtk_css_style_get_pango_attributes      (GtkCssStyle            *style);
 PangoFontDescription *  gtk_css_style_get_pango_font            (GtkCssStyle            *style);
 
+GtkCssVariableValue *   gtk_css_style_get_custom_property       (GtkCssStyle            *style,
+                                                                int                      id);
+
 GtkCssValues *gtk_css_values_new   (GtkCssValuesType  type);
 GtkCssValues *gtk_css_values_ref   (GtkCssValues     *values);
 void          gtk_css_values_unref (GtkCssValues     *values);
@@ -317,6 +332,10 @@ void gtk_css_other_values_compute_changes_and_affects (GtkCssStyle *style1,
                                                       GtkCssStyle *style2,
                                                       GtkBitmask    **changes,
                                                       GtkCssAffects *affects);
+void gtk_css_custom_values_compute_changes_and_affects (GtkCssStyle *style1,
+                                                      GtkCssStyle *style2,
+                                                      GtkBitmask    **changes,
+                                                      GtkCssAffects *affects);
 
 G_END_DECLS
 

gtk/gtkcsstransformvalue.c

@@ -273,12 +273,13 @@ gtk_css_value_transform_free (GtkCssValue *value)
 
 /* returns TRUE if dest == src */
 static gboolean
-gtk_css_transform_compute (GtkCssTransform  *dest,
-                           GtkCssTransform  *src,
-                           guint             property_id,
-                           GtkStyleProvider *provider,
-                           GtkCssStyle      *style,
-                           GtkCssStyle      *parent_style)
+gtk_css_transform_compute (GtkCssTransform   *dest,
+                           GtkCssTransform   *src,
+                           guint              property_id,
+                           GtkStyleProvider  *provider,
+                           GtkCssStyle       *style,
+                           GtkCssStyle       *parent_style,
+                           GtkCssVariableSet *variables)
 {
   dest->type = src->type;
 
@@ -288,41 +289,41 @@ gtk_css_transform_compute (GtkCssTransform  *dest,
       memcpy (dest, src, sizeof (GtkCssTransform));
       return TRUE;
     case GTK_CSS_TRANSFORM_TRANSLATE:
-      dest->translate.x = _gtk_css_value_compute (src->translate.x, property_id, provider, style, parent_style);
-      dest->translate.y = _gtk_css_value_compute (src->translate.y, property_id, provider, style, parent_style);
-      dest->translate.z = _gtk_css_value_compute (src->translate.z, property_id, provider, style, parent_style);
+      dest->translate.x = _gtk_css_value_compute (src->translate.x, property_id, provider, style, parent_style, variables);
+      dest->translate.y = _gtk_css_value_compute (src->translate.y, property_id, provider, style, parent_style, variables);
+      dest->translate.z = _gtk_css_value_compute (src->translate.z, property_id, provider, style, parent_style, variables);
       return dest->translate.x == src->translate.x
           && dest->translate.y == src->translate.y
           && dest->translate.z == src->translate.z;
     case GTK_CSS_TRANSFORM_ROTATE:
-      dest->rotate.x = _gtk_css_value_compute (src->rotate.x, property_id, provider, style, parent_style);
-      dest->rotate.y = _gtk_css_value_compute (src->rotate.y, property_id, provider, style, parent_style);
-      dest->rotate.z = _gtk_css_value_compute (src->rotate.z, property_id, provider, style, parent_style);
-      dest->rotate.angle = _gtk_css_value_compute (src->rotate.angle, property_id, provider, style, parent_style);
+      dest->rotate.x = _gtk_css_value_compute (src->rotate.x, property_id, provider, style, parent_style, variables);
+      dest->rotate.y = _gtk_css_value_compute (src->rotate.y, property_id, provider, style, parent_style, variables);
+      dest->rotate.z = _gtk_css_value_compute (src->rotate.z, property_id, provider, style, parent_style, variables);
+      dest->rotate.angle = _gtk_css_value_compute (src->rotate.angle, property_id, provider, style, parent_style, variables);
       return dest->rotate.x == src->rotate.x
           && dest->rotate.y == src->rotate.y
           && dest->rotate.z == src->rotate.z
           && dest->rotate.angle == src->rotate.angle;
     case GTK_CSS_TRANSFORM_SCALE:
-      dest->scale.x = _gtk_css_value_compute (src->scale.x, property_id, provider, style, parent_style);
-      dest->scale.y = _gtk_css_value_compute (src->scale.y, property_id, provider, style, parent_style);
-      dest->scale.z = _gtk_css_value_compute (src->scale.z, property_id, provider, style, parent_style);
+      dest->scale.x = _gtk_css_value_compute (src->scale.x, property_id, provider, style, parent_style, variables);
+      dest->scale.y = _gtk_css_value_compute (src->scale.y, property_id, provider, style, parent_style, variables);
+      dest->scale.z = _gtk_css_value_compute (src->scale.z, property_id, provider, style, parent_style, variables);
       return dest->scale.x == src->scale.x
           && dest->scale.y == src->scale.y
           && dest->scale.z == src->scale.z;
     case GTK_CSS_TRANSFORM_SKEW:
-      dest->skew.x = _gtk_css_value_compute (src->skew.x, property_id, provider, style, parent_style);
-      dest->skew.y = _gtk_css_value_compute (src->skew.y, property_id, provider, style, parent_style);
+      dest->skew.x = _gtk_css_value_compute (src->skew.x, property_id, provider, style, parent_style, variables);
+      dest->skew.y = _gtk_css_value_compute (src->skew.y, property_id, provider, style, parent_style, variables);
       return dest->skew.x == src->skew.x
           && dest->skew.y == src->skew.y;
     case GTK_CSS_TRANSFORM_SKEW_X:
-      dest->skew_x.skew = _gtk_css_value_compute (src->skew_x.skew, property_id, provider, style, parent_style);
+      dest->skew_x.skew = _gtk_css_value_compute (src->skew_x.skew, property_id, provider, style, parent_style, variables);
       return dest->skew_x.skew == src->skew_x.skew;
     case GTK_CSS_TRANSFORM_SKEW_Y:
-      dest->skew_y.skew = _gtk_css_value_compute (src->skew_y.skew, property_id, provider, style, parent_style);
+      dest->skew_y.skew = _gtk_css_value_compute (src->skew_y.skew, property_id, provider, style, parent_style, variables);
       return dest->skew_y.skew == src->skew_y.skew;
     case GTK_CSS_TRANSFORM_PERSPECTIVE:
-      dest->perspective.depth = _gtk_css_value_compute (src->perspective.depth, property_id, provider, style, parent_style);
+      dest->perspective.depth = _gtk_css_value_compute (src->perspective.depth, property_id, provider, style, parent_style, variables);
       return dest->perspective.depth == src->perspective.depth;
     case GTK_CSS_TRANSFORM_NONE:
     default:
@@ -332,11 +333,12 @@ gtk_css_transform_compute (GtkCssTransform  *dest,
 }
 
 static GtkCssValue *
-gtk_css_value_transform_compute (GtkCssValue      *value,
-                                 guint             property_id,
-                                 GtkStyleProvider *provider,
-                                 GtkCssStyle      *style,
-                                 GtkCssStyle      *parent_style)
+gtk_css_value_transform_compute (GtkCssValue       *value,
+                                 guint              property_id,
+                                 GtkStyleProvider  *provider,
+                                 GtkCssStyle       *style,
+                                 GtkCssStyle       *parent_style,
+                                 GtkCssVariableSet *variables)
 {
   GtkCssValue *result;
   gboolean changes;
@@ -356,7 +358,8 @@ gtk_css_value_transform_compute (GtkCssValue      *value,
                                              property_id,
                                              provider,
                                              style,
-                                             parent_style);
+                                             parent_style,
+                                             variables);
     }
 
   if (!changes)
@@ -798,6 +801,7 @@ static const GtkCssValueClass GTK_CSS_VALUE_TRANSFORM = {
   gtk_css_value_transform_transition,
   NULL,
   NULL,
+  NULL,
   gtk_css_value_transform_print
 };