Mint-Y-Dark: Lighten up active applet bg in panel

Use 20% mix of accent_color and bg_color3

Fixes #516

Author: clefebvre

src/Mint-Y/cinnamon/cinnamon-dark.css

@@ -1221,7 +1221,7 @@ StScrollBar {
       padding-left: 1px; }
   .grouped-window-list-item-box:hover, .grouped-window-list-item-box:focus {
     color: #e1e1e1;
-    background-color: #303036; }
+    background-color: #41584d; }
   .grouped-window-list-item-box:active, .grouped-window-list-item-box:checked {
     color: #e1e1e1;
     border-color: #35a854; }
@@ -1478,7 +1478,7 @@ StScrollBar {
     padding: 5px 0; }
   .applet-box:hover, .applet-box:checked {
     color: #ffffff;
-    background-color: #303036; }
+    background-color: #41584d; }
   .applet-box:highlight {
     background-image: none;
     border-image: none;

src/Mint-Y/cinnamon/sass/_colors.scss

@@ -6,6 +6,7 @@ $bg_color: null;
 $bg_color2: null;
 $bg_color3: null;
 $bg_color4: null;
+$panel_active_bg: null;
 $borders_color: null;
 $separator_color: null;
 $text_color: null;
@@ -26,6 +27,7 @@ $corner_bar_highlighted: null;
     $bg_color3: darken($bg_color, 22%);
     $bg_color4: darken($bg_color, 16%);
     $panel_bg: lighten($bg_color, 3%);
+    $panel_active_bg: $bg_color2;
     $borders_color: darken($bg_color, 20%);
     $separator_color: darken($bg_color, 15%);
     $text_color: #303030;
@@ -46,6 +48,7 @@ $corner_bar_highlighted: null;
     $bg_color3: lighten($bg_color, 14%);
     $bg_color4: lighten($bg_color, 9%);
     $panel_bg: darken($bg_color, 2%);
+    $panel_active_bg: mix($bg_color3, $accent_color, 80%);
     $borders_color: $bg_color2;
     $separator_color: lighten($bg_color, 2%);
     $panel_fg: #e1e1e1;

src/Mint-Y/cinnamon/sass/_common.scss

@@ -1615,7 +1615,7 @@ $base_padding: 7px;
     &:hover,
     &:focus {
       color: $panel_fg;
-      background-color: $bg_color2;
+      background-color: $panel_active_bg;
     }
 
     &:active,
@@ -1967,7 +1967,7 @@ $applet_padding: 5px;
     &:hover,
     &:checked {
       color: $noaccent_selected_fg_color;
-      background-color: $bg_color2;
+      background-color: $panel_active_bg;
     }
 
     &:highlight {