3.20: add mate-panel support (#524)

common/gtk-3.0/3.20/gtk-dark.css

@@ -3389,19 +3389,76 @@ button.documents-favorite:active:hover {
 .tr-workarea overshoot {
   border-color: transparent; }
 
+.gnome-panel-menu-bar, .gnome-panel-menu-bar menubar,
+.mate-panel-menu-bar,
+.mate-panel-menu-bar menubar {
+  background-color: rgba(43, 46, 55, 0.95); }
+
+.gnome-panel-menu-bar menubar,
+.gnome-panel-menu-bar #PanelApplet label,
+.gnome-panel-menu-bar #PanelApplet image,
+.mate-panel-menu-bar menubar,
+.mate-panel-menu-bar #PanelApplet label,
+.mate-panel-menu-bar #PanelApplet image {
+  color: #BAC3CF; }
+
+.gnome-panel-menu-bar button label, .gnome-panel-menu-bar button image,
+.gnome-panel-menu-bar #tasklist-button label,
+.gnome-panel-menu-bar #tasklist-button image,
+.mate-panel-menu-bar button label,
+.mate-panel-menu-bar button image,
+.mate-panel-menu-bar #tasklist-button label,
+.mate-panel-menu-bar #tasklist-button image {
+  color: inherit; }
+
+.gnome-panel-menu-bar .wnck-pager,
+.mate-panel-menu-bar .wnck-pager {
+  color: #5d6268;
+  background-color: rgba(20, 22, 27, 0.95); }
+  .gnome-panel-menu-bar .wnck-pager:hover,
+  .mate-panel-menu-bar .wnck-pager:hover {
+    background-color: rgba(54, 58, 70, 0.95); }
+  .gnome-panel-menu-bar .wnck-pager:selected,
+  .mate-panel-menu-bar .wnck-pager:selected {
+    color: #a9caf1;
+    background-color: #5294E2; }
+
+.gnome-panel-menu-bar na-tray-applet,
+.mate-panel-menu-bar na-tray-applet {
+  -NaTrayApplet-icon-padding: 0;
+  -NaTrayApplet-icon-size: 16px; }
+
 .xfce4-panel.panel {
   background-color: rgba(43, 46, 55, 0.95);
   text-shadow: none;
   -gtk-icon-shadow: none; }
-  .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+
-    color: #BAC3CF;
+#tasklist-button {
-    background-color: rgba(43, 46, 55, 0);
+  color: rgba(186, 195, 207, 0.8);
   border-radius: 0;
-    border: none; }
+  border: none;
-    .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
+  background-color: rgba(43, 46, 55, 0); }
+  #tasklist-button:hover {
+    color: #d8dde4;
+    background-color: rgba(0, 0, 0, 0.17); }
+  #tasklist-button:checked {
+    color: #ffffff;
+    background-color: rgba(0, 0, 0, 0.25);
+    box-shadow: inset 0 -2px #5294E2; }
+
+.gnome-panel-menu-bar button:not(#tasklist-button),
+.mate-panel-menu-bar button:not(#tasklist-button), .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+  color: #BAC3CF;
+  border-radius: 0;
+  border: none;
+  background-color: rgba(43, 46, 55, 0); }
+  .gnome-panel-menu-bar button:hover:not(#tasklist-button),
+  .mate-panel-menu-bar button:hover:not(#tasklist-button), .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
     border: none;
     background-color: rgba(65, 70, 84, 0.95); }
-    .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
+  .gnome-panel-menu-bar button:active:not(#tasklist-button),
+  .mate-panel-menu-bar button:active:not(#tasklist-button), .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .gnome-panel-menu-bar button:checked:not(#tasklist-button),
+  .mate-panel-menu-bar button:checked:not(#tasklist-button), .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
     color: #ffffff;
     border: none;
     background-color: #5294E2; }

common/gtk-3.0/3.20/gtk-darker.css

@@ -3387,19 +3387,76 @@ button.documents-favorite:active:hover {
 .tr-workarea overshoot {
   border-color: transparent; }
 
+.gnome-panel-menu-bar, .gnome-panel-menu-bar menubar,
+.mate-panel-menu-bar,
+.mate-panel-menu-bar menubar {
+  background-color: rgba(43, 46, 55, 0.95); }
+
+.gnome-panel-menu-bar menubar,
+.gnome-panel-menu-bar #PanelApplet label,
+.gnome-panel-menu-bar #PanelApplet image,
+.mate-panel-menu-bar menubar,
+.mate-panel-menu-bar #PanelApplet label,
+.mate-panel-menu-bar #PanelApplet image {
+  color: #BAC3CF; }
+
+.gnome-panel-menu-bar button label, .gnome-panel-menu-bar button image,
+.gnome-panel-menu-bar #tasklist-button label,
+.gnome-panel-menu-bar #tasklist-button image,
+.mate-panel-menu-bar button label,
+.mate-panel-menu-bar button image,
+.mate-panel-menu-bar #tasklist-button label,
+.mate-panel-menu-bar #tasklist-button image {
+  color: inherit; }
+
+.gnome-panel-menu-bar .wnck-pager,
+.mate-panel-menu-bar .wnck-pager {
+  color: #5d6268;
+  background-color: rgba(20, 22, 27, 0.95); }
+  .gnome-panel-menu-bar .wnck-pager:hover,
+  .mate-panel-menu-bar .wnck-pager:hover {
+    background-color: rgba(54, 58, 70, 0.95); }
+  .gnome-panel-menu-bar .wnck-pager:selected,
+  .mate-panel-menu-bar .wnck-pager:selected {
+    color: #a9caf1;
+    background-color: #5294E2; }
+
+.gnome-panel-menu-bar na-tray-applet,
+.mate-panel-menu-bar na-tray-applet {
+  -NaTrayApplet-icon-padding: 0;
+  -NaTrayApplet-icon-size: 16px; }
+
 .xfce4-panel.panel {
   background-color: rgba(43, 46, 55, 0.95);
   text-shadow: none;
   -gtk-icon-shadow: none; }
-  .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+
-    color: #BAC3CF;
+#tasklist-button {
-    background-color: rgba(43, 46, 55, 0);
+  color: rgba(186, 195, 207, 0.8);
   border-radius: 0;
-    border: none; }
+  border: none;
-    .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
+  background-color: rgba(43, 46, 55, 0); }
+  #tasklist-button:hover {
+    color: #d8dde4;
+    background-color: rgba(0, 0, 0, 0.17); }
+  #tasklist-button:checked {
+    color: #ffffff;
+    background-color: rgba(0, 0, 0, 0.25);
+    box-shadow: inset 0 -2px #5294E2; }
+
+.gnome-panel-menu-bar button:not(#tasklist-button),
+.mate-panel-menu-bar button:not(#tasklist-button), .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+  color: #BAC3CF;
+  border-radius: 0;
+  border: none;
+  background-color: rgba(43, 46, 55, 0); }
+  .gnome-panel-menu-bar button:hover:not(#tasklist-button),
+  .mate-panel-menu-bar button:hover:not(#tasklist-button), .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
     border: none;
     background-color: rgba(65, 70, 84, 0.95); }
-    .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
+  .gnome-panel-menu-bar button:active:not(#tasklist-button),
+  .mate-panel-menu-bar button:active:not(#tasklist-button), .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .gnome-panel-menu-bar button:checked:not(#tasklist-button),
+  .mate-panel-menu-bar button:checked:not(#tasklist-button), .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
     color: #ffffff;
     border: none;
     background-color: #5294E2; }

common/gtk-3.0/3.20/gtk-solid-dark.css

@@ -3389,19 +3389,76 @@ button.documents-favorite:active:hover {
 .tr-workarea overshoot {
   border-color: transparent; }
 
+.gnome-panel-menu-bar, .gnome-panel-menu-bar menubar,
+.mate-panel-menu-bar,
+.mate-panel-menu-bar menubar {
+  background-color: #2b2e37; }
+
+.gnome-panel-menu-bar menubar,
+.gnome-panel-menu-bar #PanelApplet label,
+.gnome-panel-menu-bar #PanelApplet image,
+.mate-panel-menu-bar menubar,
+.mate-panel-menu-bar #PanelApplet label,
+.mate-panel-menu-bar #PanelApplet image {
+  color: #BAC3CF; }
+
+.gnome-panel-menu-bar button label, .gnome-panel-menu-bar button image,
+.gnome-panel-menu-bar #tasklist-button label,
+.gnome-panel-menu-bar #tasklist-button image,
+.mate-panel-menu-bar button label,
+.mate-panel-menu-bar button image,
+.mate-panel-menu-bar #tasklist-button label,
+.mate-panel-menu-bar #tasklist-button image {
+  color: inherit; }
+
+.gnome-panel-menu-bar .wnck-pager,
+.mate-panel-menu-bar .wnck-pager {
+  color: #5d6268;
+  background-color: #14161b; }
+  .gnome-panel-menu-bar .wnck-pager:hover,
+  .mate-panel-menu-bar .wnck-pager:hover {
+    background-color: #363a46; }
+  .gnome-panel-menu-bar .wnck-pager:selected,
+  .mate-panel-menu-bar .wnck-pager:selected {
+    color: #a9caf1;
+    background-color: #5294E2; }
+
+.gnome-panel-menu-bar na-tray-applet,
+.mate-panel-menu-bar na-tray-applet {
+  -NaTrayApplet-icon-padding: 0;
+  -NaTrayApplet-icon-size: 16px; }
+
 .xfce4-panel.panel {
   background-color: #2b2e37;
   text-shadow: none;
   -gtk-icon-shadow: none; }
-  .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+
-    color: #BAC3CF;
+#tasklist-button {
-    background-color: rgba(43, 46, 55, 0);
+  color: rgba(186, 195, 207, 0.8);
   border-radius: 0;
-    border: none; }
+  border: none;
-    .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
+  background-color: rgba(43, 46, 55, 0); }
+  #tasklist-button:hover {
+    color: #d8dde4;
+    background-color: rgba(0, 0, 0, 0.17); }
+  #tasklist-button:checked {
+    color: #ffffff;
+    background-color: rgba(0, 0, 0, 0.25);
+    box-shadow: inset 0 -2px #5294E2; }
+
+.gnome-panel-menu-bar button:not(#tasklist-button),
+.mate-panel-menu-bar button:not(#tasklist-button), .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+  color: #BAC3CF;
+  border-radius: 0;
+  border: none;
+  background-color: rgba(43, 46, 55, 0); }
+  .gnome-panel-menu-bar button:hover:not(#tasklist-button),
+  .mate-panel-menu-bar button:hover:not(#tasklist-button), .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
     border: none;
     background-color: #414654; }
-    .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
+  .gnome-panel-menu-bar button:active:not(#tasklist-button),
+  .mate-panel-menu-bar button:active:not(#tasklist-button), .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .gnome-panel-menu-bar button:checked:not(#tasklist-button),
+  .mate-panel-menu-bar button:checked:not(#tasklist-button), .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
     color: #ffffff;
     border: none;
     background-color: #5294E2; }

common/gtk-3.0/3.20/gtk-solid-darker.css

@@ -3387,19 +3387,76 @@ button.documents-favorite:active:hover {
 .tr-workarea overshoot {
   border-color: transparent; }
 
+.gnome-panel-menu-bar, .gnome-panel-menu-bar menubar,
+.mate-panel-menu-bar,
+.mate-panel-menu-bar menubar {
+  background-color: #2b2e37; }
+
+.gnome-panel-menu-bar menubar,
+.gnome-panel-menu-bar #PanelApplet label,
+.gnome-panel-menu-bar #PanelApplet image,
+.mate-panel-menu-bar menubar,
+.mate-panel-menu-bar #PanelApplet label,
+.mate-panel-menu-bar #PanelApplet image {
+  color: #BAC3CF; }
+
+.gnome-panel-menu-bar button label, .gnome-panel-menu-bar button image,
+.gnome-panel-menu-bar #tasklist-button label,
+.gnome-panel-menu-bar #tasklist-button image,
+.mate-panel-menu-bar button label,
+.mate-panel-menu-bar button image,
+.mate-panel-menu-bar #tasklist-button label,
+.mate-panel-menu-bar #tasklist-button image {
+  color: inherit; }
+
+.gnome-panel-menu-bar .wnck-pager,
+.mate-panel-menu-bar .wnck-pager {
+  color: #5d6268;
+  background-color: #14161b; }
+  .gnome-panel-menu-bar .wnck-pager:hover,
+  .mate-panel-menu-bar .wnck-pager:hover {
+    background-color: #363a46; }
+  .gnome-panel-menu-bar .wnck-pager:selected,
+  .mate-panel-menu-bar .wnck-pager:selected {
+    color: #a9caf1;
+    background-color: #5294E2; }
+
+.gnome-panel-menu-bar na-tray-applet,
+.mate-panel-menu-bar na-tray-applet {
+  -NaTrayApplet-icon-padding: 0;
+  -NaTrayApplet-icon-size: 16px; }
+
 .xfce4-panel.panel {
   background-color: #2b2e37;
   text-shadow: none;
   -gtk-icon-shadow: none; }
-  .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+
-    color: #BAC3CF;
+#tasklist-button {
-    background-color: rgba(43, 46, 55, 0);
+  color: rgba(186, 195, 207, 0.8);
   border-radius: 0;
-    border: none; }
+  border: none;
-    .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
+  background-color: rgba(43, 46, 55, 0); }
+  #tasklist-button:hover {
+    color: #d8dde4;
+    background-color: rgba(0, 0, 0, 0.17); }
+  #tasklist-button:checked {
+    color: #ffffff;
+    background-color: rgba(0, 0, 0, 0.25);
+    box-shadow: inset 0 -2px #5294E2; }
+
+.gnome-panel-menu-bar button:not(#tasklist-button),
+.mate-panel-menu-bar button:not(#tasklist-button), .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+  color: #BAC3CF;
+  border-radius: 0;
+  border: none;
+  background-color: rgba(43, 46, 55, 0); }
+  .gnome-panel-menu-bar button:hover:not(#tasklist-button),
+  .mate-panel-menu-bar button:hover:not(#tasklist-button), .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
     border: none;
     background-color: #414654; }
-    .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
+  .gnome-panel-menu-bar button:active:not(#tasklist-button),
+  .mate-panel-menu-bar button:active:not(#tasklist-button), .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .gnome-panel-menu-bar button:checked:not(#tasklist-button),
+  .mate-panel-menu-bar button:checked:not(#tasklist-button), .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
     color: #ffffff;
     border: none;
     background-color: #5294E2; }

common/gtk-3.0/3.20/gtk-solid.css

@@ -3391,19 +3391,76 @@ button.documents-favorite:active:hover {
 .tr-workarea overshoot {
   border-color: transparent; }
 
+.gnome-panel-menu-bar, .gnome-panel-menu-bar menubar,
+.mate-panel-menu-bar,
+.mate-panel-menu-bar menubar {
+  background-color: #2b2e37; }
+
+.gnome-panel-menu-bar menubar,
+.gnome-panel-menu-bar #PanelApplet label,
+.gnome-panel-menu-bar #PanelApplet image,
+.mate-panel-menu-bar menubar,
+.mate-panel-menu-bar #PanelApplet label,
+.mate-panel-menu-bar #PanelApplet image {
+  color: #BAC3CF; }
+
+.gnome-panel-menu-bar button label, .gnome-panel-menu-bar button image,
+.gnome-panel-menu-bar #tasklist-button label,
+.gnome-panel-menu-bar #tasklist-button image,
+.mate-panel-menu-bar button label,
+.mate-panel-menu-bar button image,
+.mate-panel-menu-bar #tasklist-button label,
+.mate-panel-menu-bar #tasklist-button image {
+  color: inherit; }
+
+.gnome-panel-menu-bar .wnck-pager,
+.mate-panel-menu-bar .wnck-pager {
+  color: #5d6268;
+  background-color: #14161b; }
+  .gnome-panel-menu-bar .wnck-pager:hover,
+  .mate-panel-menu-bar .wnck-pager:hover {
+    background-color: #363a46; }
+  .gnome-panel-menu-bar .wnck-pager:selected,
+  .mate-panel-menu-bar .wnck-pager:selected {
+    color: #a9caf1;
+    background-color: #5294E2; }
+
+.gnome-panel-menu-bar na-tray-applet,
+.mate-panel-menu-bar na-tray-applet {
+  -NaTrayApplet-icon-padding: 0;
+  -NaTrayApplet-icon-size: 16px; }
+
 .xfce4-panel.panel {
   background-color: #2b2e37;
   text-shadow: none;
   -gtk-icon-shadow: none; }
-  .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+
-    color: #BAC3CF;
+#tasklist-button {
-    background-color: rgba(43, 46, 55, 0);
+  color: rgba(186, 195, 207, 0.8);
   border-radius: 0;
-    border: none; }
+  border: none;
-    .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
+  background-color: rgba(43, 46, 55, 0); }
+  #tasklist-button:hover {
+    color: #d8dde4;
+    background-color: rgba(0, 0, 0, 0.17); }
+  #tasklist-button:checked {
+    color: #ffffff;
+    background-color: rgba(0, 0, 0, 0.25);
+    box-shadow: inset 0 -2px #5294E2; }
+
+.gnome-panel-menu-bar button:not(#tasklist-button),
+.mate-panel-menu-bar button:not(#tasklist-button), .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+  color: #BAC3CF;
+  border-radius: 0;
+  border: none;
+  background-color: rgba(43, 46, 55, 0); }
+  .gnome-panel-menu-bar button:hover:not(#tasklist-button),
+  .mate-panel-menu-bar button:hover:not(#tasklist-button), .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
     border: none;
     background-color: #414654; }
-    .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
+  .gnome-panel-menu-bar button:active:not(#tasklist-button),
+  .mate-panel-menu-bar button:active:not(#tasklist-button), .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .gnome-panel-menu-bar button:checked:not(#tasklist-button),
+  .mate-panel-menu-bar button:checked:not(#tasklist-button), .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
     color: #ffffff;
     border: none;
     background-color: #5294E2; }

common/gtk-3.0/3.20/gtk.css

@@ -3391,19 +3391,76 @@ button.documents-favorite:active:hover {
 .tr-workarea overshoot {
   border-color: transparent; }
 
+.gnome-panel-menu-bar, .gnome-panel-menu-bar menubar,
+.mate-panel-menu-bar,
+.mate-panel-menu-bar menubar {
+  background-color: rgba(43, 46, 55, 0.95); }
+
+.gnome-panel-menu-bar menubar,
+.gnome-panel-menu-bar #PanelApplet label,
+.gnome-panel-menu-bar #PanelApplet image,
+.mate-panel-menu-bar menubar,
+.mate-panel-menu-bar #PanelApplet label,
+.mate-panel-menu-bar #PanelApplet image {
+  color: #BAC3CF; }
+
+.gnome-panel-menu-bar button label, .gnome-panel-menu-bar button image,
+.gnome-panel-menu-bar #tasklist-button label,
+.gnome-panel-menu-bar #tasklist-button image,
+.mate-panel-menu-bar button label,
+.mate-panel-menu-bar button image,
+.mate-panel-menu-bar #tasklist-button label,
+.mate-panel-menu-bar #tasklist-button image {
+  color: inherit; }
+
+.gnome-panel-menu-bar .wnck-pager,
+.mate-panel-menu-bar .wnck-pager {
+  color: #5d6268;
+  background-color: rgba(20, 22, 27, 0.95); }
+  .gnome-panel-menu-bar .wnck-pager:hover,
+  .mate-panel-menu-bar .wnck-pager:hover {
+    background-color: rgba(54, 58, 70, 0.95); }
+  .gnome-panel-menu-bar .wnck-pager:selected,
+  .mate-panel-menu-bar .wnck-pager:selected {
+    color: #a9caf1;
+    background-color: #5294E2; }
+
+.gnome-panel-menu-bar na-tray-applet,
+.mate-panel-menu-bar na-tray-applet {
+  -NaTrayApplet-icon-padding: 0;
+  -NaTrayApplet-icon-size: 16px; }
+
 .xfce4-panel.panel {
   background-color: rgba(43, 46, 55, 0.95);
   text-shadow: none;
   -gtk-icon-shadow: none; }
-  .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+
-    color: #BAC3CF;
+#tasklist-button {
-    background-color: rgba(43, 46, 55, 0);
+  color: rgba(186, 195, 207, 0.8);
   border-radius: 0;
-    border: none; }
+  border: none;
-    .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
+  background-color: rgba(43, 46, 55, 0); }
+  #tasklist-button:hover {
+    color: #d8dde4;
+    background-color: rgba(0, 0, 0, 0.17); }
+  #tasklist-button:checked {
+    color: #ffffff;
+    background-color: rgba(0, 0, 0, 0.25);
+    box-shadow: inset 0 -2px #5294E2; }
+
+.gnome-panel-menu-bar button:not(#tasklist-button),
+.mate-panel-menu-bar button:not(#tasklist-button), .xfce4-panel.panel button.flat, .xfce4-panel.panel button.sidebar-button {
+  color: #BAC3CF;
+  border-radius: 0;
+  border: none;
+  background-color: rgba(43, 46, 55, 0); }
+  .gnome-panel-menu-bar button:hover:not(#tasklist-button),
+  .mate-panel-menu-bar button:hover:not(#tasklist-button), .xfce4-panel.panel button.flat:hover, .xfce4-panel.panel button.sidebar-button:hover {
     border: none;
     background-color: rgba(65, 70, 84, 0.95); }
-    .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
+  .gnome-panel-menu-bar button:active:not(#tasklist-button),
+  .mate-panel-menu-bar button:active:not(#tasklist-button), .xfce4-panel.panel button.flat:active, .xfce4-panel.panel button.sidebar-button:active, .gnome-panel-menu-bar button:checked:not(#tasklist-button),
+  .mate-panel-menu-bar button:checked:not(#tasklist-button), .xfce4-panel.panel button.flat:checked, .xfce4-panel.panel button.sidebar-button:checked {
     color: #ffffff;
     border: none;
     background-color: #5294E2; }

common/gtk-3.0/3.20/sass/_applications.scss

@@ -396,65 +396,46 @@ button.documents-favorite:active:hover {
 }
 
 //
-// Fallback Mode/Budgie Panel
+// Mate/Gnome Flashback Panel
 //
-//.gnome-panel-menu-bar,
+.gnome-panel-menu-bar,
-//PanelApplet > menubar,
+.mate-panel-menu-bar {
-//PanelToplevel,
+
-//PanelWidget,
+  &, menubar { background-color: $panel_bg; }
-//PanelAppletFrame,
+
-//PanelApplet {
+  menubar,
-//  color: $panel_fg;
+  #PanelApplet label,
-//  background-image: linear-gradient(to bottom, $panel_bg);
+  #PanelApplet image { color: $panel_fg; }
-//}
+
-//
+  // Panel buttons
-//PanelApplet button, PanelApplet button:backdrop {
+  button:not(#tasklist-button) {
-//  padding: 4px;
+    @extend %panelbutton;
-//  border: 2px solid transparent;
+  }
-//  border-radius: 0;
+
-//  background-image: none;
+  button,
-//  background-color: transparent;
+  #tasklist-button {
-//  color: $panel_fg;
+    label, image { color: inherit; }
-//}
+  }
-//
+
-//PanelApplet button:hover {
+  .wnck-pager {
-//  color: lighten($panel_fg, 10%);
+    color: mix($panel_fg, black, 50%);
-//  background-color: transparentize(black, 0.83);
+    background-color: darken($panel_bg, 10%);
-//  border-color: transparentize(black, 0.83);
+
-//}
+    &:hover {
-//
+      background-color: lighten($panel_bg, 5%);
-//PanelApplet button:active, PanelApplet button:active:backdrop,
+    }
-//PanelApplet button:checked, PanelApplet button:checked:backdrop {
+
-//  background-clip: padding-box;
+    &:selected {
-//  color: $selected_fg_color;
+      color: lighten($selected_bg_color, 20%);
-//  background-color: transparentize(black, 0.75);
+      background-color: $selected_bg_color;
-//  border-radius: 0;
+    }
-//  border-color: transparentize(black, 0.75);
+  }
-//  box-shadow: inset 0 -2px $selected_bg_color;
+
-//}
+  na-tray-applet {
-//
+    -NaTrayApplet-icon-padding: 0;
-//PanelApplet:hover {
+    -NaTrayApplet-icon-size: 16px;
-//  color: $selected_fg_color;
+  }
-//}
+}
-//
-//PanelApplet:active,
-//PanelApplet:hover:active {
-//  color: $selected_bg_color;
-//}
-//
-//WnckPager {
-//  color: mix($panel_fg, black, 50%);
-//  &:selected { color: $selected_bg_color }
-//}
-//
-//NaTrayApplet {
-//  -NaTrayApplet-icon-padding: 12;
-//  -NaTrayApplet-icon-size: 16;
-//}
-//
-//ClockBox {
-//  color: $panel_fg;
-//}
 
 // Xfce Panel
 .xfce4-panel.panel {
@@ -463,11 +444,32 @@ button.documents-favorite:active:hover {
   text-shadow: none;
   -gtk-icon-shadow: none;
 
-  button.flat {
+  button.flat { @extend %panelbutton; }
-    color: $panel_fg;
+}
-    background-color: transparentize($panel_bg, 1);
+
+#tasklist-button {
+  color: transparentize($panel_fg, 0.2);
   border-radius: 0;
   border: none;
+  background-color: transparentize($panel_bg, 1);
+
+  &:hover {
+    color: lighten($panel_fg, 10%);
+    background-color: transparentize(black, 0.83);
+  }
+
+  &:checked {
+    color: $selected_fg_color;
+    background-color: transparentize(black, 0.75);
+    box-shadow: inset 0 -2px $selected_bg_color;
+  }
+}
+
+%panelbutton {
+  color: $panel_fg;
+  border-radius: 0;
+  border: none;
+  background-color: transparentize($panel_bg, 1);
 
   &:hover {
     border: none;
@@ -479,7 +481,6 @@ button.documents-favorite:active:hover {
     background-color: $selected_bg_color;
   }
 }
-}
 
 //
 // Floating Bar