diff --git a/gtk/gtkcsscolorvalue.c b/gtk/gtkcsscolorvalue.c
index 6246475c9f..8f31ae0765 100644
--- a/gtk/gtkcsscolorvalue.c
+++ b/gtk/gtkcsscolorvalue.c
@@ -874,28 +874,6 @@ parse_comma (GtkCssTokenSource *source)
   return TRUE;
 }
 
-static gboolean
-parse_number (GtkCssTokenSource *source,
-              double            *d)
-{
-  const GtkCssToken *token;
-
-  token = gtk_css_token_source_get_token (source);
-  if (gtk_css_token_is (token, GTK_CSS_TOKEN_INTEGER) ||
-      gtk_css_token_is (token, GTK_CSS_TOKEN_NUMBER))
-    {
-      *d = token->number.number;
-      gtk_css_token_source_consume_token (source);
-      return TRUE;
-    }
-  else
-    {
-      gtk_css_token_source_error (source, "Expected a number.");
-      gtk_css_token_source_consume_all (source);
-      return FALSE;
-    }
-}
-
 static gboolean
 parse_percentage (GtkCssTokenSource *source,
                   double            *d)
@@ -982,11 +960,11 @@ gtk_css_color_value_token_parse (GtkCssTokenSource *source)
             }
           else
             {
-              if (!parse_number (source, &rgba.red) ||
+              if (!gtk_css_token_source_consume_number (source, &rgba.red) ||
                   !parse_comma (source) ||
-                  !parse_number (source, &rgba.green) ||
+                  !gtk_css_token_source_consume_number (source, &rgba.green) ||
                   !parse_comma (source) ||
-                  !parse_number (source, &rgba.blue))
+                  !gtk_css_token_source_consume_number (source, &rgba.blue))
                 return NULL;
               rgba.red = CLAMP (rgba.red, 0, 255.0) / 255.0;
               rgba.green = CLAMP (rgba.green, 0, 255.0) / 255.0;
@@ -996,7 +974,7 @@ gtk_css_color_value_token_parse (GtkCssTokenSource *source)
           if (has_alpha)
             {
               if (!parse_comma (source) ||
-                  !parse_number (source, &rgba.alpha))
+                  !gtk_css_token_source_consume_number (source, &rgba.alpha))
                 return NULL;
               rgba.alpha = CLAMP (rgba.alpha, 0, 1.0);
             }
@@ -1044,7 +1022,7 @@ gtk_css_color_value_token_parse (GtkCssTokenSource *source)
           if (child == NULL)
             return NULL;
           if (!parse_comma (source) ||
-              !parse_number (source, &d))
+              !gtk_css_token_source_consume_number (source, &d))
             {
               _gtk_css_value_unref (child);
               return NULL;
@@ -1065,7 +1043,7 @@ gtk_css_color_value_token_parse (GtkCssTokenSource *source)
           if (child == NULL)
             return NULL;
           if (!parse_comma (source) ||
-              !parse_number (source, &d))
+              !gtk_css_token_source_consume_number (source, &d))
             {
               _gtk_css_value_unref (child);
               return NULL;
@@ -1092,7 +1070,7 @@ gtk_css_color_value_token_parse (GtkCssTokenSource *source)
               return NULL;
             }
           if (!parse_comma (source) ||
-              !parse_number (source, &d))
+              !gtk_css_token_source_consume_number (source, &d))
             {
               _gtk_css_value_unref (child1);
               _gtk_css_value_unref (child2);
diff --git a/gtk/gtkcsseasevalue.c b/gtk/gtkcsseasevalue.c
index ebf626451e..842a4d9a5f 100644
--- a/gtk/gtkcsseasevalue.c
+++ b/gtk/gtkcsseasevalue.c
@@ -333,28 +333,19 @@ token_parse_cubic_bezier (GtkCssTokenSource *source,
                           gpointer           data)
 {
   double *numbers = data;
-  const GtkCssToken *token;
 
-  token = gtk_css_token_source_get_token (source);
-  if (gtk_css_token_is (token, GTK_CSS_TOKEN_INTEGER) ||
-      gtk_css_token_is (token, GTK_CSS_TOKEN_NUMBER))
+  if (!gtk_css_token_source_consume_number (source, &numbers[n]))
+    return FALSE;
+
+  /* XXX: This error is too late */
+  if (n % 2 == 0 &&
+      (numbers[n] < 0 || numbers[n] > 1.0))
     {
-      numbers[n] = token->number.number;
-      if (n % 2 == 0 &&
-          (numbers[n] < 0 || numbers[n] > 1.0))
-        {
-          gtk_css_token_source_error (source, "Value %g out of range. Must be from 0.0 to 1.0", numbers[n]);
-          return FALSE;
-        }
-      gtk_css_token_source_consume_token (source);
-      return TRUE;
-    }
-  else
-    {
-      gtk_css_token_source_error (source, "Expected a number");
-      gtk_css_token_source_consume_all (source);
+      gtk_css_token_source_error (source, "Value %g out of range. Must be from 0.0 to 1.0", numbers[n]);
       return FALSE;
     }
+
+  return TRUE;
 }
 
 static gboolean
diff --git a/gtk/gtkcsstokensource.c b/gtk/gtkcsstokensource.c
index 58d9586442..ffb3b5658c 100644
--- a/gtk/gtkcsstokensource.c
+++ b/gtk/gtkcsstokensource.c
@@ -21,6 +21,7 @@
 
 #include "gtkcsstokensourceprivate.h"
 
+#include "gtkcssnumbervalueprivate.h"
 #include "gtkcssprovider.h"
 
 typedef struct _GtkCssTokenSourceTokenizer GtkCssTokenSourceTokenizer;
@@ -392,6 +393,32 @@ gtk_css_token_source_consume_function (GtkCssTokenSource      *source,
   return result;
 }
 
+gboolean
+gtk_css_token_source_consume_number (GtkCssTokenSource *source,
+                                     double            *number)
+{
+  const GtkCssToken *token;
+  GtkCssValue *value;
+
+  token = gtk_css_token_source_get_token (source);
+  if (gtk_css_token_is (token, GTK_CSS_TOKEN_NUMBER) ||
+      gtk_css_token_is (token, GTK_CSS_TOKEN_INTEGER))
+    {
+      *number = token->number.number;
+      gtk_css_token_source_consume_token (source);
+      return TRUE;
+    }
+
+  /* because CSS allows calc() in numbers. Go CSS! */
+  value = gtk_css_number_value_token_parse (source, GTK_CSS_PARSE_NUMBER);
+  if (value == NULL)
+    return FALSE;
+
+  *number = _gtk_css_number_value_get (value, 100);
+  _gtk_css_value_unref (value);
+  return TRUE;
+}
+
 GtkCssTokenType
 gtk_css_token_get_pending_block (GtkCssTokenSource *source)
 {
diff --git a/gtk/gtkcsstokensourceprivate.h b/gtk/gtkcsstokensourceprivate.h
index 9efc060819..8547611955 100644
--- a/gtk/gtkcsstokensourceprivate.h
+++ b/gtk/gtkcsstokensourceprivate.h
@@ -73,6 +73,8 @@ gboolean                gtk_css_token_source_consume_function   (GtkCssTokenSour
                                                                  guint                   max_args,
                                                                  gboolean (* parse_func) (GtkCssTokenSource *, guint, gpointer),
                                                                  gpointer                data);
+gboolean                gtk_css_token_source_consume_number     (GtkCssTokenSource      *source,
+                                                                 double                 *number);
 
 void                    gtk_css_token_source_emit_error         (GtkCssTokenSource      *source,
                                                                  const GError           *error);