diff --git a/gtk/theme/Adwaita/_drawing.scss b/gtk/theme/Adwaita/_drawing.scss
index 6ae9b541ea..69c7c263d9 100644
--- a/gtk/theme/Adwaita/_drawing.scss
+++ b/gtk/theme/Adwaita/_drawing.scss
@@ -275,8 +275,7 @@
     color: $tc;
     outline-color: transparentize($tc, 0.7);
     border-color: if($c != $bg_color, _border_color($c), $borders_color);
-    background-image: none;
-    background-color: darken($c, 6%);
+    background-image: image(darken($c, 6%));
     @include _shadows(inset 0 1px transparentize($_hilight_color, 1), $_button_edge);
 
     text-shadow: none;
@@ -291,8 +290,7 @@
     label, & { color: if($tc != $fg_color, mix($tc, $_bg, 50%), $insensitive_fg_color); }
 
     border-color: if($c != $bg_color, _border_color($c), $insensitive_borders_color);
-    background-color: $_bg;
-    background-image: none;
+    background-image: image($_bg);
     text-shadow: none;
     -gtk-icon-shadow: none;
     // white with 0 alpha to avoid an ugly transition, since no color means
@@ -309,8 +307,7 @@
     label, & { color: if($c != $bg_color, mix($tc, $_bg, 60%), $insensitive_fg_color); }
 
     border-color: $_bc;
-    background-color: $_bg;
-    background-image: none;
+    background-image: image($_bg);
     // white with 0 alpha to avoid an ugly transition, since no color means
     // black with 0 alpha
     @include _shadows(inset 0 1px transparentize(white, 1), $_button_edge);
@@ -326,7 +323,6 @@
     label, & { color: if($tc != $fg_color, mix($tc, $_bg, 80%), $backdrop_fg_color); }
 
     border-color: if($c != $bg_color, $_bc, $backdrop_borders_color);
-    background-color: transparent;
     background-image: image($_bg);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -343,8 +339,7 @@
     label, & { color: if($tc != $fg_color, mix($tc, $_bg, 80%), $backdrop_fg_color); }
 
     border-color: if($c != $bg_color, $_bc, $backdrop_borders_color);
-    background-color: $_bg;
-    background-image: none;
+    background-image: image($_bg);
     @include _shadows(inset 0 1px transparentize(white, 1), $_blank_edge);
   }
 
@@ -359,8 +354,7 @@
     label, & { color: if($c != $bg_color, mix($tc, $_bg, 35%), $backdrop_insensitive_color); }
 
     border-color: if($c != $bg_color, $_bc, $backdrop_borders_color);
-    background-color: $_bg;
-    background-image: none;
+    background-image: image($_bg);
     text-shadow: none;
     -gtk-icon-shadow: none;
     // white with 0 alpha to avoid an ugly transition, since no color means
@@ -379,8 +373,7 @@
     label { color: if($c != $bg_color, mix($tc, $_bg, 35%), $backdrop_insensitive_color); }
 
     border-color: if($c != $bg_color, $_bc, $backdrop_borders_color);
-    background-color: $_bg;
-    background-image: none;
+    background-image: image($_bg);
     @include _shadows(inset 0 1px transparentize(white, 1), $_blank_edge);
   }
 
diff --git a/gtk/theme/Adwaita/gtk-contained-dark.css b/gtk/theme/Adwaita/gtk-contained-dark.css
index f5bcde2acd..fd14f42268 100644
--- a/gtk/theme/Adwaita/gtk-contained-dark.css
+++ b/gtk/theme/Adwaita/gtk-contained-dark.css
@@ -448,8 +448,7 @@ button {
     color: #eeeeec;
     outline-color: rgba(238, 238, 236, 0.3);
     border-color: #1b1f20;
-    background-image: none;
-    background-color: #25292b;
+    background-image: image(#25292b);
     box-shadow: inset 0 1px rgba(255, 255, 255, 0);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -458,7 +457,6 @@ button {
   button:backdrop.flat,
   button:backdrop {
     border-color: #202425;
-    background-color: transparent;
     background-image: image(#33393b);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -477,8 +475,7 @@ button {
     button:backdrop:active,
     button:backdrop:checked {
       border-color: #202425;
-      background-color: #272c2d;
-      background-image: none;
+      background-image: image(#272c2d);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       notebook > header > tabs > arrow:backdrop:active label, button.sidebar-button:backdrop:active label, button.titlebutton:backdrop:active label, notebook > header > tabs > arrow:backdrop:active, button.sidebar-button:backdrop:active, button.titlebutton:backdrop:active, notebook > header > tabs > arrow:backdrop:checked label, button.sidebar-button:backdrop:checked label, button.titlebutton:backdrop:checked label, notebook > header > tabs > arrow:backdrop:checked, button.sidebar-button:backdrop:checked, button.titlebutton:backdrop:checked, notebook > header > tabs > arrow:backdrop:active label, button.titlebutton:backdrop:active label, notebook > header > tabs > arrow:backdrop:active, button.titlebutton:backdrop:active, notebook > header > tabs > arrow:backdrop:checked label, button.titlebutton:backdrop:checked label, notebook > header > tabs > arrow:backdrop:checked, button.titlebutton:backdrop:checked,
       button:backdrop.flat:active label,
@@ -494,8 +491,7 @@ button {
     button:backdrop.flat:disabled,
     button:backdrop:disabled {
       border-color: #202425;
-      background-color: #2d3234;
-      background-image: none;
+      background-image: image(#2d3234);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -511,8 +507,7 @@ button {
       button:backdrop:disabled:active,
       button:backdrop:disabled:checked {
         border-color: #202425;
-        background-color: #272c2d;
-        background-image: none;
+        background-image: image(#272c2d);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
         notebook > header > tabs > arrow:backdrop:disabled:active label, button.sidebar-button:backdrop:disabled:active label, button.titlebutton:backdrop:disabled:active label, notebook > header > tabs > arrow:backdrop:disabled:checked label, button.sidebar-button:backdrop:disabled:checked label, button.titlebutton:backdrop:disabled:checked label, notebook > header > tabs > arrow:backdrop:disabled:active label, button.titlebutton:backdrop:disabled:active label, notebook > header > tabs > arrow:backdrop:disabled:checked label, button.titlebutton:backdrop:disabled:checked label,
         button:backdrop.flat:disabled:active label,
@@ -533,8 +528,7 @@ button {
   notebook > header > tabs > arrow:disabled, button.titlebutton:disabled,
   button:disabled {
     border-color: #1b1f20;
-    background-color: #2d3234;
-    background-image: none;
+    background-image: image(#2d3234);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -546,8 +540,7 @@ button {
     button:disabled:active,
     button:disabled:checked {
       border-color: #1b1f20;
-      background-color: #232628;
-      background-image: none;
+      background-image: image(#232628);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       notebook > header > tabs > arrow:disabled:active label, button.titlebutton:disabled:active label, notebook > header > tabs > arrow:disabled:active, button.titlebutton:disabled:active, notebook > header > tabs > arrow:disabled:checked label, button.titlebutton:disabled:checked label, notebook > header > tabs > arrow:disabled:checked, button.titlebutton:disabled:checked,
       button:disabled:active label,
@@ -793,8 +786,7 @@ button.suggested-action {
     color: white;
     outline-color: rgba(255, 255, 255, 0.3);
     border-color: #0f2b48;
-    background-image: none;
-    background-color: #1b4e83;
+    background-image: image(#1b4e83);
     box-shadow: inset 0 1px rgba(255, 255, 255, 0);
     text-shadow: none;
     -gtk-icon-shadow: none; }
@@ -802,7 +794,6 @@ button.suggested-action {
   button.suggested-action:backdrop,
   button.suggested-action.flat:backdrop {
     border-color: #0f2b48;
-    background-color: transparent;
     background-image: image(#215d9c);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -819,8 +810,7 @@ button.suggested-action {
     button.suggested-action.flat:backdrop:active,
     button.suggested-action.flat:backdrop:checked {
       border-color: #0f2b48;
-      background-color: #1d4b7b;
-      background-image: none;
+      background-image: image(#1d4b7b);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       .selection-mode button.titlebutton:backdrop:active label, .selection-mode button.titlebutton:backdrop:active, .selection-mode button.titlebutton:backdrop:checked label, .selection-mode button.titlebutton:backdrop:checked,
       button.suggested-action:backdrop:active label,
@@ -836,8 +826,7 @@ button.suggested-action {
     button.suggested-action:backdrop:disabled,
     button.suggested-action.flat:backdrop:disabled {
       border-color: #202425;
-      background-color: #2d3234;
-      background-image: none;
+      background-image: image(#2d3234);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -853,8 +842,7 @@ button.suggested-action {
       button.suggested-action.flat:backdrop:disabled:active,
       button.suggested-action.flat:backdrop:disabled:checked {
         border-color: #0f2b48;
-        background-color: #1d4b7b;
-        background-image: none;
+        background-image: image(#1d4b7b);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
         .selection-mode button.titlebutton:backdrop:disabled:active label, .selection-mode button.titlebutton:backdrop:disabled:checked label,
         button.suggested-action:backdrop:disabled:active label,
@@ -875,8 +863,7 @@ button.suggested-action {
     color: rgba(33, 93, 156, 0.8); }
   button.suggested-action:disabled {
     border-color: #1b1f20;
-    background-color: #2d3234;
-    background-image: none;
+    background-image: image(#2d3234);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -886,8 +873,7 @@ button.suggested-action {
     button.suggested-action:disabled:active,
     button.suggested-action:disabled:checked {
       border-color: #0f2b48;
-      background-color: #1b4672;
-      background-image: none;
+      background-image: image(#1b4672);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       button.suggested-action:disabled:active label,
       button.suggested-action:disabled:active,
@@ -982,15 +968,13 @@ button.destructive-action {
     color: white;
     outline-color: rgba(255, 255, 255, 0.3);
     border-color: #760909;
-    background-image: none;
-    background-color: #b90e0e;
+    background-image: image(#b90e0e);
     box-shadow: inset 0 1px rgba(255, 255, 255, 0);
     text-shadow: none;
     -gtk-icon-shadow: none; }
   button.destructive-action:backdrop,
   button.destructive-action.flat:backdrop {
     border-color: #760909;
-    background-color: transparent;
     background-image: image(#d51010);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -1005,8 +989,7 @@ button.destructive-action {
     button.destructive-action.flat:backdrop:active,
     button.destructive-action.flat:backdrop:checked {
       border-color: #760909;
-      background-color: #a71112;
-      background-image: none;
+      background-image: image(#a71112);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       button.destructive-action:backdrop:active label,
       button.destructive-action:backdrop:active,
@@ -1020,8 +1003,7 @@ button.destructive-action {
     button.destructive-action:backdrop:disabled,
     button.destructive-action.flat:backdrop:disabled {
       border-color: #202425;
-      background-color: #2d3234;
-      background-image: none;
+      background-image: image(#2d3234);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -1035,8 +1017,7 @@ button.destructive-action {
       button.destructive-action.flat:backdrop:disabled:active,
       button.destructive-action.flat:backdrop:disabled:checked {
         border-color: #760909;
-        background-color: #a71112;
-        background-image: none;
+        background-image: image(#a71112);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
         button.destructive-action:backdrop:disabled:active label,
         button.destructive-action:backdrop:disabled:checked label,
@@ -1055,8 +1036,7 @@ button.destructive-action {
     color: rgba(213, 16, 16, 0.8); }
   button.destructive-action:disabled {
     border-color: #1b1f20;
-    background-color: #2d3234;
-    background-image: none;
+    background-image: image(#2d3234);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -1066,8 +1046,7 @@ button.destructive-action {
     button.destructive-action:disabled:active,
     button.destructive-action:disabled:checked {
       border-color: #760909;
-      background-color: #9e1011;
-      background-image: none;
+      background-image: image(#9e1011);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       button.destructive-action:disabled:active label,
       button.destructive-action:disabled:active,
@@ -1217,15 +1196,13 @@ button.needs-attention > image, stacksidebar row.needs-attention > label {
     color: #eeeeec;
     outline-color: rgba(238, 238, 236, 0.3);
     border-color: #1b1f20;
-    background-image: none;
-    background-color: #25292b;
+    background-image: image(#25292b);
     box-shadow: inset 0 1px rgba(255, 255, 255, 0);
     text-shadow: none;
     -gtk-icon-shadow: none; }
   .inline-toolbar toolbutton > button:disabled {
     border-color: #1b1f20;
-    background-color: #2d3234;
-    background-image: none;
+    background-image: image(#2d3234);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -1233,14 +1210,12 @@ button.needs-attention > image, stacksidebar row.needs-attention > label {
       color: #919494; }
     .inline-toolbar toolbutton > button:disabled:active, .inline-toolbar toolbutton > button:disabled:checked {
       border-color: #1b1f20;
-      background-color: #232628;
-      background-image: none;
+      background-image: image(#232628);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       .inline-toolbar toolbutton > button:disabled:active label, .inline-toolbar toolbutton > button:disabled:active, .inline-toolbar toolbutton > button:disabled:checked label, .inline-toolbar toolbutton > button:disabled:checked {
         color: #919494; }
   .inline-toolbar toolbutton > button:backdrop {
     border-color: #202425;
-    background-color: transparent;
     background-image: image(#33393b);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -1249,15 +1224,13 @@ button.needs-attention > image, stacksidebar row.needs-attention > label {
       color: #919494; }
     .inline-toolbar toolbutton > button:backdrop:active, .inline-toolbar toolbutton > button:backdrop:checked {
       border-color: #202425;
-      background-color: #272c2d;
-      background-image: none;
+      background-image: image(#272c2d);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       .inline-toolbar toolbutton > button:backdrop:active label, .inline-toolbar toolbutton > button:backdrop:active, .inline-toolbar toolbutton > button:backdrop:checked label, .inline-toolbar toolbutton > button:backdrop:checked {
         color: #919494; }
     .inline-toolbar toolbutton > button:backdrop:disabled {
       border-color: #202425;
-      background-color: #2d3234;
-      background-image: none;
+      background-image: image(#2d3234);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -1265,8 +1238,7 @@ button.needs-attention > image, stacksidebar row.needs-attention > label {
         color: #566164; }
       .inline-toolbar toolbutton > button:backdrop:disabled:active, .inline-toolbar toolbutton > button:backdrop:disabled:checked {
         border-color: #202425;
-        background-color: #272c2d;
-        background-image: none;
+        background-image: image(#272c2d);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
         .inline-toolbar toolbutton > button:backdrop:disabled:active label, .inline-toolbar toolbutton > button:backdrop:disabled:checked label {
           color: #566164; }
@@ -1787,8 +1759,7 @@ headerbar {
         color: #ffffff;
         outline-color: rgba(255, 255, 255, 0.3);
         border-color: #0f2b48;
-        background-image: none;
-        background-color: #1b4e83;
+        background-image: image(#1b4e83);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0);
         text-shadow: none;
         -gtk-icon-shadow: none; }
@@ -1796,7 +1767,6 @@ headerbar {
       headerbar.selection-mode button:backdrop.flat,
       headerbar.selection-mode button:backdrop {
         border-color: #0f2b48;
-        background-color: transparent;
         background-image: image(#215d9c);
         text-shadow: none;
         -gtk-icon-shadow: none;
@@ -1815,8 +1785,7 @@ headerbar {
         headerbar.selection-mode button:backdrop:active,
         headerbar.selection-mode button:backdrop:checked {
           border-color: #0f2b48;
-          background-color: #1d4b7b;
-          background-image: none;
+          background-image: image(#1d4b7b);
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
           border-color: #0f2b48; }
           .selection-mode.titlebar:not(headerbar) button:backdrop.flat:active label, .selection-mode.titlebar:not(headerbar) button:backdrop.flat:active, .selection-mode.titlebar:not(headerbar) button:backdrop.flat:checked label, .selection-mode.titlebar:not(headerbar) button:backdrop.flat:checked, .selection-mode.titlebar:not(headerbar) button:backdrop:active label, .selection-mode.titlebar:not(headerbar) button:backdrop:active, .selection-mode.titlebar:not(headerbar) button:backdrop:checked label, .selection-mode.titlebar:not(headerbar) button:backdrop:checked,
@@ -1833,8 +1802,7 @@ headerbar {
         headerbar.selection-mode button:backdrop.flat:disabled,
         headerbar.selection-mode button:backdrop:disabled {
           border-color: #0f2b48;
-          background-color: #21558b;
-          background-image: none;
+          background-image: image(#21558b);
           text-shadow: none;
           -gtk-icon-shadow: none;
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
@@ -1851,8 +1819,7 @@ headerbar {
           headerbar.selection-mode button:backdrop:disabled:active,
           headerbar.selection-mode button:backdrop:disabled:checked {
             border-color: #0f2b48;
-            background-color: #1d4b7b;
-            background-image: none;
+            background-image: image(#1d4b7b);
             box-shadow: inset 0 1px rgba(255, 255, 255, 0);
             border-color: #0f2b48; }
             .selection-mode.titlebar:not(headerbar) button:backdrop.flat:disabled:active label, .selection-mode.titlebar:not(headerbar) button:backdrop.flat:disabled:checked label, .selection-mode.titlebar:not(headerbar) button:backdrop:disabled:active label, .selection-mode.titlebar:not(headerbar) button:backdrop:disabled:checked label,
@@ -1874,8 +1841,7 @@ headerbar {
       .selection-mode.titlebar:not(headerbar) button:disabled,
       headerbar.selection-mode button:disabled {
         border-color: #0f2b48;
-        background-color: #21558b;
-        background-image: none;
+        background-image: image(#21558b);
         text-shadow: none;
         -gtk-icon-shadow: none;
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -1887,8 +1853,7 @@ headerbar {
         headerbar.selection-mode button:disabled:active,
         headerbar.selection-mode button:disabled:checked {
           border-color: #0f2b48;
-          background-color: #1b4672;
-          background-image: none;
+          background-image: image(#1b4672);
           box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
           .selection-mode.titlebar:not(headerbar) button:disabled:active label, .selection-mode.titlebar:not(headerbar) button:disabled:active, .selection-mode.titlebar:not(headerbar) button:disabled:checked label, .selection-mode.titlebar:not(headerbar) button:disabled:checked,
           headerbar.selection-mode button:disabled:active label,
@@ -1923,8 +1888,7 @@ headerbar {
           color: #eeeeec;
           outline-color: rgba(238, 238, 236, 0.3);
           border-color: #1b1f20;
-          background-image: none;
-          background-color: #25292b;
+          background-image: image(#25292b);
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
           text-shadow: none;
           -gtk-icon-shadow: none;
@@ -1932,8 +1896,7 @@ headerbar {
         .selection-mode.titlebar:not(headerbar) button.suggested-action:disabled,
         headerbar.selection-mode button.suggested-action:disabled {
           border-color: #1b1f20;
-          background-color: #2d3234;
-          background-image: none;
+          background-image: image(#2d3234);
           text-shadow: none;
           -gtk-icon-shadow: none;
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
@@ -1945,7 +1908,6 @@ headerbar {
         .selection-mode.titlebar:not(headerbar) button.suggested-action:backdrop,
         headerbar.selection-mode button.suggested-action:backdrop {
           border-color: #202425;
-          background-color: transparent;
           background-image: image(#33393b);
           text-shadow: none;
           -gtk-icon-shadow: none;
@@ -1958,8 +1920,7 @@ headerbar {
         .selection-mode.titlebar:not(headerbar) button.suggested-action:backdrop:disabled,
         headerbar.selection-mode button.suggested-action:backdrop:disabled {
           border-color: #202425;
-          background-color: #2d3234;
-          background-image: none;
+          background-image: image(#2d3234);
           text-shadow: none;
           -gtk-icon-shadow: none;
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
@@ -2752,8 +2713,7 @@ switch {
     border: 1px solid #0f2b48; }
   switch:disabled slider {
     border-color: #1b1f20;
-    background-color: #2d3234;
-    background-image: none;
+    background-image: image(#2d3234);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -2762,7 +2722,6 @@ switch {
   switch:backdrop slider {
     transition: 200ms ease-out;
     border-color: #202425;
-    background-color: transparent;
     background-image: image(#33393b);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -2773,8 +2732,7 @@ switch {
     border-color: #0f2b48; }
   switch:backdrop:disabled slider {
     border-color: #202425;
-    background-color: #2d3234;
-    background-image: none;
+    background-image: image(#2d3234);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -2861,16 +2819,14 @@ radio {
     color: #eeeeec;
     outline-color: rgba(238, 238, 236, 0.3);
     border-color: #1b1f20;
-    background-image: none;
-    background-color: #25292b;
+    background-image: image(#25292b);
     box-shadow: inset 0 1px rgba(255, 255, 255, 0);
     text-shadow: none;
     -gtk-icon-shadow: none; }
   check:disabled,
   radio:disabled {
     border-color: #1b1f20;
-    background-color: #2d3234;
-    background-image: none;
+    background-image: image(#2d3234);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -2881,7 +2837,6 @@ radio {
   check:backdrop,
   radio:backdrop {
     border-color: #202425;
-    background-color: transparent;
     background-image: image(#33393b);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -2894,8 +2849,7 @@ radio {
     check:backdrop:disabled,
     radio:backdrop:disabled {
       border-color: #202425;
-      background-color: #2d3234;
-      background-image: none;
+      background-image: image(#2d3234);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -3127,8 +3081,7 @@ scale {
       border-color: #0f2b48; }
     scale slider:disabled {
       border-color: #1b1f20;
-      background-color: #2d3234;
-      background-image: none;
+      background-image: image(#2d3234);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -3137,7 +3090,6 @@ scale {
     scale slider:backdrop {
       transition: 200ms ease-out;
       border-color: #202425;
-      background-color: transparent;
       background-image: image(#33393b);
       text-shadow: none;
       -gtk-icon-shadow: none;
@@ -3146,8 +3098,7 @@ scale {
         color: #919494; }
       scale slider:backdrop:disabled {
         border-color: #202425;
-        background-color: #2d3234;
-        background-image: none;
+        background-image: image(#2d3234);
         text-shadow: none;
         -gtk-icon-shadow: none;
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -4244,15 +4195,13 @@ infobar {
         color: #ffffff;
         outline-color: rgba(255, 255, 255, 0.3);
         border-color: #0f2b48;
-        background-image: none;
-        background-color: #1b4e83;
+        background-image: image(#1b4e83);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0);
         text-shadow: none;
         -gtk-icon-shadow: none; }
       infobar.info button:disabled, infobar.question button:disabled, infobar.warning button:disabled, infobar.error button:disabled {
         border-color: #0f2b48;
-        background-color: #21558b;
-        background-image: none;
+        background-image: image(#21558b);
         text-shadow: none;
         -gtk-icon-shadow: none;
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -4260,7 +4209,6 @@ infobar {
           color: #90aac5; }
       infobar.info button:backdrop, infobar.question button:backdrop, infobar.warning button:backdrop, infobar.error button:backdrop {
         border-color: #0f2b48;
-        background-color: transparent;
         background-image: image(#215d9c);
         text-shadow: none;
         -gtk-icon-shadow: none;
@@ -4270,8 +4218,7 @@ infobar {
           color: #d3dfeb; }
         infobar.info button:backdrop:disabled, infobar.question button:backdrop:disabled, infobar.warning button:backdrop:disabled, infobar.error button:backdrop:disabled {
           border-color: #0f2b48;
-          background-color: #21558b;
-          background-image: none;
+          background-image: image(#21558b);
           text-shadow: none;
           -gtk-icon-shadow: none;
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
@@ -4381,7 +4328,6 @@ colorswatch#add-color-button {
       box-shadow: inset 0 1px rgba(255, 255, 255, 0.05); }
     colorswatch#add-color-button overlay:backdrop {
       border-color: #202425;
-      background-color: transparent;
       background-image: image(#33393b);
       text-shadow: none;
       -gtk-icon-shadow: none;
diff --git a/gtk/theme/Adwaita/gtk-contained.css b/gtk/theme/Adwaita/gtk-contained.css
index 34219889db..f1e0022b07 100644
--- a/gtk/theme/Adwaita/gtk-contained.css
+++ b/gtk/theme/Adwaita/gtk-contained.css
@@ -448,8 +448,7 @@ button {
     color: #2e3436;
     outline-color: rgba(46, 52, 54, 0.3);
     border-color: #b6b6b3;
-    background-image: none;
-    background-color: #d9d9d7;
+    background-image: image(#d9d9d7);
     box-shadow: inset 0 1px rgba(255, 255, 255, 0);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -458,7 +457,6 @@ button {
   button:backdrop.flat,
   button:backdrop {
     border-color: #c0c0bd;
-    background-color: transparent;
     background-image: image(#e8e8e7);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -477,8 +475,7 @@ button {
     button:backdrop:active,
     button:backdrop:checked {
       border-color: #c0c0bd;
-      background-color: #d7d7d7;
-      background-image: none;
+      background-image: image(#d7d7d7);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       notebook > header > tabs > arrow:backdrop:active label, button.sidebar-button:backdrop:active label, button.titlebutton:backdrop:active label, notebook > header > tabs > arrow:backdrop:active, button.sidebar-button:backdrop:active, button.titlebutton:backdrop:active, notebook > header > tabs > arrow:backdrop:checked label, button.sidebar-button:backdrop:checked label, button.titlebutton:backdrop:checked label, notebook > header > tabs > arrow:backdrop:checked, button.sidebar-button:backdrop:checked, button.titlebutton:backdrop:checked, notebook > header > tabs > arrow:backdrop:active label, button.titlebutton:backdrop:active label, notebook > header > tabs > arrow:backdrop:active, button.titlebutton:backdrop:active, notebook > header > tabs > arrow:backdrop:checked label, button.titlebutton:backdrop:checked label, notebook > header > tabs > arrow:backdrop:checked, button.titlebutton:backdrop:checked,
       button:backdrop.flat:active label,
@@ -494,8 +491,7 @@ button {
     button:backdrop.flat:disabled,
     button:backdrop:disabled {
       border-color: #c0c0bd;
-      background-color: #f1f1f1;
-      background-image: none;
+      background-image: image(#f1f1f1);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -511,8 +507,7 @@ button {
       button:backdrop:disabled:active,
       button:backdrop:disabled:checked {
         border-color: #c0c0bd;
-        background-color: #d7d7d7;
-        background-image: none;
+        background-image: image(#d7d7d7);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
         notebook > header > tabs > arrow:backdrop:disabled:active label, button.sidebar-button:backdrop:disabled:active label, button.titlebutton:backdrop:disabled:active label, notebook > header > tabs > arrow:backdrop:disabled:checked label, button.sidebar-button:backdrop:disabled:checked label, button.titlebutton:backdrop:disabled:checked label, notebook > header > tabs > arrow:backdrop:disabled:active label, button.titlebutton:backdrop:disabled:active label, notebook > header > tabs > arrow:backdrop:disabled:checked label, button.titlebutton:backdrop:disabled:checked label,
         button:backdrop.flat:disabled:active label,
@@ -533,8 +528,7 @@ button {
   notebook > header > tabs > arrow:disabled, button.titlebutton:disabled,
   button:disabled {
     border-color: #b6b6b3;
-    background-color: #f1f1f1;
-    background-image: none;
+    background-image: image(#f1f1f1);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -546,8 +540,7 @@ button {
     button:disabled:active,
     button:disabled:checked {
       border-color: #b6b6b3;
-      background-color: #d7d7d7;
-      background-image: none;
+      background-image: image(#d7d7d7);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       notebook > header > tabs > arrow:disabled:active label, button.titlebutton:disabled:active label, notebook > header > tabs > arrow:disabled:active, button.titlebutton:disabled:active, notebook > header > tabs > arrow:disabled:checked label, button.titlebutton:disabled:checked label, notebook > header > tabs > arrow:disabled:checked, button.titlebutton:disabled:checked,
       button:disabled:active label,
@@ -796,8 +789,7 @@ button.suggested-action {
     color: white;
     outline-color: rgba(255, 255, 255, 0.3);
     border-color: #215d9c;
-    background-image: none;
-    background-color: #3180d4;
+    background-image: image(#3180d4);
     box-shadow: inset 0 1px rgba(255, 255, 255, 0);
     text-shadow: none;
     -gtk-icon-shadow: none; }
@@ -805,7 +797,6 @@ button.suggested-action {
   button.suggested-action:backdrop,
   button.suggested-action.flat:backdrop {
     border-color: #4a90d9;
-    background-color: transparent;
     background-image: image(#4a90d9);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -822,8 +813,7 @@ button.suggested-action {
     button.suggested-action.flat:backdrop:active,
     button.suggested-action.flat:backdrop:checked {
       border-color: #438cd8;
-      background-color: #438cd8;
-      background-image: none;
+      background-image: image(#438cd8);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       .selection-mode button.titlebutton:backdrop:active label, .selection-mode button.titlebutton:backdrop:active, .selection-mode button.titlebutton:backdrop:checked label, .selection-mode button.titlebutton:backdrop:checked,
       button.suggested-action:backdrop:active label,
@@ -839,8 +829,7 @@ button.suggested-action {
     button.suggested-action:backdrop:disabled,
     button.suggested-action.flat:backdrop:disabled {
       border-color: #c0c0bd;
-      background-color: #f1f1f1;
-      background-image: none;
+      background-image: image(#f1f1f1);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -856,8 +845,7 @@ button.suggested-action {
       button.suggested-action.flat:backdrop:disabled:active,
       button.suggested-action.flat:backdrop:disabled:checked {
         border-color: #438cd8;
-        background-color: #438cd8;
-        background-image: none;
+        background-image: image(#438cd8);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
         .selection-mode button.titlebutton:backdrop:disabled:active label, .selection-mode button.titlebutton:backdrop:disabled:checked label,
         button.suggested-action:backdrop:disabled:active label,
@@ -878,8 +866,7 @@ button.suggested-action {
     color: rgba(74, 144, 217, 0.8); }
   button.suggested-action:disabled {
     border-color: #b6b6b3;
-    background-color: #f1f1f1;
-    background-image: none;
+    background-image: image(#f1f1f1);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -889,8 +876,7 @@ button.suggested-action {
     button.suggested-action:disabled:active,
     button.suggested-action:disabled:checked {
       border-color: #215d9c;
-      background-color: #438cd8;
-      background-image: none;
+      background-image: image(#438cd8);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       button.suggested-action:disabled:active label,
       button.suggested-action:disabled:active,
@@ -985,15 +971,13 @@ button.destructive-action {
     color: white;
     outline-color: rgba(255, 255, 255, 0.3);
     border-color: #a60c0c;
-    background-image: none;
-    background-color: #e81111;
+    background-image: image(#e81111);
     box-shadow: inset 0 1px rgba(255, 255, 255, 0);
     text-shadow: none;
     -gtk-icon-shadow: none; }
   button.destructive-action:backdrop,
   button.destructive-action.flat:backdrop {
     border-color: #ef2929;
-    background-color: transparent;
     background-image: image(#ef2929);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -1008,8 +992,7 @@ button.destructive-action {
     button.destructive-action.flat:backdrop:active,
     button.destructive-action.flat:backdrop:checked {
       border-color: #ee2323;
-      background-color: #ee2323;
-      background-image: none;
+      background-image: image(#ee2323);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       button.destructive-action:backdrop:active label,
       button.destructive-action:backdrop:active,
@@ -1023,8 +1006,7 @@ button.destructive-action {
     button.destructive-action:backdrop:disabled,
     button.destructive-action.flat:backdrop:disabled {
       border-color: #c0c0bd;
-      background-color: #f1f1f1;
-      background-image: none;
+      background-image: image(#f1f1f1);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -1038,8 +1020,7 @@ button.destructive-action {
       button.destructive-action.flat:backdrop:disabled:active,
       button.destructive-action.flat:backdrop:disabled:checked {
         border-color: #ee2323;
-        background-color: #ee2323;
-        background-image: none;
+        background-image: image(#ee2323);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
         button.destructive-action:backdrop:disabled:active label,
         button.destructive-action:backdrop:disabled:checked label,
@@ -1058,8 +1039,7 @@ button.destructive-action {
     color: rgba(239, 41, 41, 0.8); }
   button.destructive-action:disabled {
     border-color: #b6b6b3;
-    background-color: #f1f1f1;
-    background-image: none;
+    background-image: image(#f1f1f1);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -1069,8 +1049,7 @@ button.destructive-action {
     button.destructive-action:disabled:active,
     button.destructive-action:disabled:checked {
       border-color: #a60c0c;
-      background-color: #ee2323;
-      background-image: none;
+      background-image: image(#ee2323);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       button.destructive-action:disabled:active label,
       button.destructive-action:disabled:active,
@@ -1220,15 +1199,13 @@ button.needs-attention > image, stacksidebar row.needs-attention > label {
     color: #2e3436;
     outline-color: rgba(46, 52, 54, 0.3);
     border-color: #b6b6b3;
-    background-image: none;
-    background-color: #d9d9d7;
+    background-image: image(#d9d9d7);
     box-shadow: inset 0 1px rgba(255, 255, 255, 0);
     text-shadow: none;
     -gtk-icon-shadow: none; }
   .inline-toolbar toolbutton > button:disabled {
     border-color: #b6b6b3;
-    background-color: #f1f1f1;
-    background-image: none;
+    background-image: image(#f1f1f1);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -1236,14 +1213,12 @@ button.needs-attention > image, stacksidebar row.needs-attention > label {
       color: #8b8e8f; }
     .inline-toolbar toolbutton > button:disabled:active, .inline-toolbar toolbutton > button:disabled:checked {
       border-color: #b6b6b3;
-      background-color: #d7d7d7;
-      background-image: none;
+      background-image: image(#d7d7d7);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       .inline-toolbar toolbutton > button:disabled:active label, .inline-toolbar toolbutton > button:disabled:active, .inline-toolbar toolbutton > button:disabled:checked label, .inline-toolbar toolbutton > button:disabled:checked {
         color: #8b8e8f; }
   .inline-toolbar toolbutton > button:backdrop {
     border-color: #c0c0bd;
-    background-color: transparent;
     background-image: image(#e8e8e7);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -1252,15 +1227,13 @@ button.needs-attention > image, stacksidebar row.needs-attention > label {
       color: #8b8e8f; }
     .inline-toolbar toolbutton > button:backdrop:active, .inline-toolbar toolbutton > button:backdrop:checked {
       border-color: #c0c0bd;
-      background-color: #d7d7d7;
-      background-image: none;
+      background-image: image(#d7d7d7);
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
       .inline-toolbar toolbutton > button:backdrop:active label, .inline-toolbar toolbutton > button:backdrop:active, .inline-toolbar toolbutton > button:backdrop:checked label, .inline-toolbar toolbutton > button:backdrop:checked {
         color: #8b8e8f; }
     .inline-toolbar toolbutton > button:backdrop:disabled {
       border-color: #c0c0bd;
-      background-color: #f1f1f1;
-      background-image: none;
+      background-image: image(#f1f1f1);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -1268,8 +1241,7 @@ button.needs-attention > image, stacksidebar row.needs-attention > label {
         color: #c3c3c0; }
       .inline-toolbar toolbutton > button:backdrop:disabled:active, .inline-toolbar toolbutton > button:backdrop:disabled:checked {
         border-color: #c0c0bd;
-        background-color: #d7d7d7;
-        background-image: none;
+        background-image: image(#d7d7d7);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
         .inline-toolbar toolbutton > button:backdrop:disabled:active label, .inline-toolbar toolbutton > button:backdrop:disabled:checked label {
           color: #c3c3c0; }
@@ -1796,8 +1768,7 @@ headerbar {
         color: #ffffff;
         outline-color: rgba(255, 255, 255, 0.3);
         border-color: #215d9c;
-        background-image: none;
-        background-color: #3180d4;
+        background-image: image(#3180d4);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0);
         text-shadow: none;
         -gtk-icon-shadow: none; }
@@ -1805,7 +1776,6 @@ headerbar {
       headerbar.selection-mode button:backdrop.flat,
       headerbar.selection-mode button:backdrop {
         border-color: #4a90d9;
-        background-color: transparent;
         background-image: image(#4a90d9);
         text-shadow: none;
         -gtk-icon-shadow: none;
@@ -1824,8 +1794,7 @@ headerbar {
         headerbar.selection-mode button:backdrop:active,
         headerbar.selection-mode button:backdrop:checked {
           border-color: #438cd8;
-          background-color: #438cd8;
-          background-image: none;
+          background-image: image(#438cd8);
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
           border-color: #184472; }
           .selection-mode.titlebar:not(headerbar) button:backdrop.flat:active label, .selection-mode.titlebar:not(headerbar) button:backdrop.flat:active, .selection-mode.titlebar:not(headerbar) button:backdrop.flat:checked label, .selection-mode.titlebar:not(headerbar) button:backdrop.flat:checked, .selection-mode.titlebar:not(headerbar) button:backdrop:active label, .selection-mode.titlebar:not(headerbar) button:backdrop:active, .selection-mode.titlebar:not(headerbar) button:backdrop:checked label, .selection-mode.titlebar:not(headerbar) button:backdrop:checked,
@@ -1842,8 +1811,7 @@ headerbar {
         headerbar.selection-mode button:backdrop.flat:disabled,
         headerbar.selection-mode button:backdrop:disabled {
           border-color: #65a1df;
-          background-color: #65a1df;
-          background-image: none;
+          background-image: image(#65a1df);
           text-shadow: none;
           -gtk-icon-shadow: none;
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
@@ -1860,8 +1828,7 @@ headerbar {
           headerbar.selection-mode button:backdrop:disabled:active,
           headerbar.selection-mode button:backdrop:disabled:checked {
             border-color: #438cd8;
-            background-color: #438cd8;
-            background-image: none;
+            background-image: image(#438cd8);
             box-shadow: inset 0 1px rgba(255, 255, 255, 0);
             border-color: #184472; }
             .selection-mode.titlebar:not(headerbar) button:backdrop.flat:disabled:active label, .selection-mode.titlebar:not(headerbar) button:backdrop.flat:disabled:checked label, .selection-mode.titlebar:not(headerbar) button:backdrop:disabled:active label, .selection-mode.titlebar:not(headerbar) button:backdrop:disabled:checked label,
@@ -1883,8 +1850,7 @@ headerbar {
       .selection-mode.titlebar:not(headerbar) button:disabled,
       headerbar.selection-mode button:disabled {
         border-color: #215d9c;
-        background-color: #65a1df;
-        background-image: none;
+        background-image: image(#65a1df);
         text-shadow: none;
         -gtk-icon-shadow: none;
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -1896,8 +1862,7 @@ headerbar {
         headerbar.selection-mode button:disabled:active,
         headerbar.selection-mode button:disabled:checked {
           border-color: #215d9c;
-          background-color: #438cd8;
-          background-image: none;
+          background-image: image(#438cd8);
           box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
           .selection-mode.titlebar:not(headerbar) button:disabled:active label, .selection-mode.titlebar:not(headerbar) button:disabled:active, .selection-mode.titlebar:not(headerbar) button:disabled:checked label, .selection-mode.titlebar:not(headerbar) button:disabled:checked,
           headerbar.selection-mode button:disabled:active label,
@@ -1932,8 +1897,7 @@ headerbar {
           color: #2e3436;
           outline-color: rgba(46, 52, 54, 0.3);
           border-color: #b6b6b3;
-          background-image: none;
-          background-color: #d9d9d7;
+          background-image: image(#d9d9d7);
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
           text-shadow: none;
           -gtk-icon-shadow: none;
@@ -1941,8 +1905,7 @@ headerbar {
         .selection-mode.titlebar:not(headerbar) button.suggested-action:disabled,
         headerbar.selection-mode button.suggested-action:disabled {
           border-color: #b6b6b3;
-          background-color: #f1f1f1;
-          background-image: none;
+          background-image: image(#f1f1f1);
           text-shadow: none;
           -gtk-icon-shadow: none;
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
@@ -1954,7 +1917,6 @@ headerbar {
         .selection-mode.titlebar:not(headerbar) button.suggested-action:backdrop,
         headerbar.selection-mode button.suggested-action:backdrop {
           border-color: #c0c0bd;
-          background-color: transparent;
           background-image: image(#e8e8e7);
           text-shadow: none;
           -gtk-icon-shadow: none;
@@ -1967,8 +1929,7 @@ headerbar {
         .selection-mode.titlebar:not(headerbar) button.suggested-action:backdrop:disabled,
         headerbar.selection-mode button.suggested-action:backdrop:disabled {
           border-color: #c0c0bd;
-          background-color: #f1f1f1;
-          background-image: none;
+          background-image: image(#f1f1f1);
           text-shadow: none;
           -gtk-icon-shadow: none;
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
@@ -2768,8 +2729,7 @@ switch {
     border: 1px solid #184472; }
   switch:disabled slider {
     border-color: #b6b6b3;
-    background-color: #f1f1f1;
-    background-image: none;
+    background-image: image(#f1f1f1);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -2778,7 +2738,6 @@ switch {
   switch:backdrop slider {
     transition: 200ms ease-out;
     border-color: #c0c0bd;
-    background-color: transparent;
     background-image: image(#e8e8e7);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -2789,8 +2748,7 @@ switch {
     border-color: #4a90d9; }
   switch:backdrop:disabled slider {
     border-color: #c0c0bd;
-    background-color: #f1f1f1;
-    background-image: none;
+    background-image: image(#f1f1f1);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -2888,16 +2846,14 @@ radio {
     color: #2e3436;
     outline-color: rgba(46, 52, 54, 0.3);
     border-color: #b6b6b3;
-    background-image: none;
-    background-color: #d9d9d7;
+    background-image: image(#d9d9d7);
     box-shadow: inset 0 1px rgba(255, 255, 255, 0);
     text-shadow: none;
     -gtk-icon-shadow: none; }
   check:disabled,
   radio:disabled {
     border-color: #b6b6b3;
-    background-color: #f1f1f1;
-    background-image: none;
+    background-image: image(#f1f1f1);
     text-shadow: none;
     -gtk-icon-shadow: none;
     box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -2908,7 +2864,6 @@ radio {
   check:backdrop,
   radio:backdrop {
     border-color: #c0c0bd;
-    background-color: transparent;
     background-image: image(#e8e8e7);
     text-shadow: none;
     -gtk-icon-shadow: none;
@@ -2921,8 +2876,7 @@ radio {
     check:backdrop:disabled,
     radio:backdrop:disabled {
       border-color: #c0c0bd;
-      background-color: #f1f1f1;
-      background-image: none;
+      background-image: image(#f1f1f1);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -3158,8 +3112,7 @@ scale {
       border-color: #184472; }
     scale slider:disabled {
       border-color: #b6b6b3;
-      background-color: #f1f1f1;
-      background-image: none;
+      background-image: image(#f1f1f1);
       text-shadow: none;
       -gtk-icon-shadow: none;
       box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -3168,7 +3121,6 @@ scale {
     scale slider:backdrop {
       transition: 200ms ease-out;
       border-color: #c0c0bd;
-      background-color: transparent;
       background-image: image(#e8e8e7);
       text-shadow: none;
       -gtk-icon-shadow: none;
@@ -3177,8 +3129,7 @@ scale {
         color: #8b8e8f; }
       scale slider:backdrop:disabled {
         border-color: #c0c0bd;
-        background-color: #f1f1f1;
-        background-image: none;
+        background-image: image(#f1f1f1);
         text-shadow: none;
         -gtk-icon-shadow: none;
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -4275,15 +4226,13 @@ infobar {
         color: #ffffff;
         outline-color: rgba(255, 255, 255, 0.3);
         border-color: #215d9c;
-        background-image: none;
-        background-color: #3180d4;
+        background-image: image(#3180d4);
         box-shadow: inset 0 1px rgba(255, 255, 255, 0);
         text-shadow: none;
         -gtk-icon-shadow: none; }
       infobar.info button:disabled, infobar.question button:disabled, infobar.warning button:disabled, infobar.error button:disabled {
         border-color: #215d9c;
-        background-color: #65a1df;
-        background-image: none;
+        background-image: image(#65a1df);
         text-shadow: none;
         -gtk-icon-shadow: none;
         box-shadow: inset 0 1px rgba(255, 255, 255, 0); }
@@ -4291,7 +4240,6 @@ infobar {
           color: #b2d0ef; }
       infobar.info button:backdrop, infobar.question button:backdrop, infobar.warning button:backdrop, infobar.error button:backdrop {
         border-color: #4a90d9;
-        background-color: transparent;
         background-image: image(#4a90d9);
         text-shadow: none;
         -gtk-icon-shadow: none;
@@ -4301,8 +4249,7 @@ infobar {
           color: #dbe9f7; }
         infobar.info button:backdrop:disabled, infobar.question button:backdrop:disabled, infobar.warning button:backdrop:disabled, infobar.error button:backdrop:disabled {
           border-color: #65a1df;
-          background-color: #65a1df;
-          background-image: none;
+          background-image: image(#65a1df);
           text-shadow: none;
           -gtk-icon-shadow: none;
           box-shadow: inset 0 1px rgba(255, 255, 255, 0);
@@ -4412,7 +4359,6 @@ colorswatch#add-color-button {
       box-shadow: inset 0 1px white; }
     colorswatch#add-color-button overlay:backdrop {
       border-color: #c0c0bd;
-      background-color: transparent;
       background-image: image(#e8e8e7);
       text-shadow: none;
       -gtk-icon-shadow: none;