Adwaita: tone down sidebar selected items

Fixes https://gitlab.gnome.org/Teams/Design/os-mockups/issues/16

(as long as apps set the sidebar row class to .sidebar-row like
Nautilus does)

gtk/theme/Adwaita/_common.scss

@@ -3777,6 +3777,26 @@ row {
   }
 
   &:selected { @extend %selected_items; }
+  
+  &.sidebar-row { // https://gitlab.gnome.org/Teams/Design/os-mockups/issues/16
+
+    &:selected {
+      color: $text_color;
+      background-color: darken($sidebar_bg_color, 10%);
+      label { color: $text_color; }
+            
+      &.has-open-popup,
+        &:hover { 
+          background-color: if(variant == light, transparentize($fg_color, 0.7), transparentize($fg_color, 0.75));
+      }
+      &:backdrop { 
+        color: $backdrop_text_color;
+        background-color: darken($backdrop_sidebar_bg_color, 10%); 
+        label { color: $backdrop_text_color; }
+      }
+
+    }
+  }
 }
 
 

gtk/theme/Adwaita/gtk-contained-dark.css

@@ -1600,6 +1600,16 @@ row.activatable:selected.has-open-popup, row.activatable:selected:hover { backgr
 
 row.activatable:selected:backdrop { background-color: #15539e; }
 
+row.sidebar-row:selected { color: white; background-color: #181818; }
+
+row.sidebar-row:selected label { color: white; }
+
+row.sidebar-row:selected.has-open-popup, row.sidebar-row:selected:hover { background-color: rgba(238, 238, 236, 0.25); }
+
+row.sidebar-row:selected:backdrop { color: #d6d6d6; background-color: #191919; }
+
+row.sidebar-row:selected:backdrop label { color: #d6d6d6; }
+
 /********************* App Notifications * */
 .app-notification, .app-notification.frame { padding: 10px; border-radius: 0 0 5px 5px; background-color: rgba(53, 53, 53, 0.7); background-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.2), transparent 2px); background-clip: padding-box; }
 

gtk/theme/Adwaita/gtk-contained.css

@@ -1616,6 +1616,16 @@ row.activatable:selected.has-open-popup, row.activatable:selected:hover { backgr
 
 row.activatable:selected:backdrop { background-color: #3584e4; }
 
+row.sidebar-row:selected { color: black; background-color: #e4dede; }
+
+row.sidebar-row:selected label { color: black; }
+
+row.sidebar-row:selected.has-open-popup, row.sidebar-row:selected:hover { background-color: rgba(46, 52, 54, 0.25); }
+
+row.sidebar-row:selected:backdrop { color: #323232; background-color: #e1e1dd; }
+
+row.sidebar-row:selected:backdrop label { color: #323232; }
+
 /********************* App Notifications * */
 .app-notification, .app-notification.frame { padding: 10px; border-radius: 0 0 5px 5px; background-color: rgba(53, 53, 53, 0.7); background-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.2), transparent 2px); background-clip: padding-box; }