[gnome-shell-sass] theme: Add :active styling to message-close and media control buttons

[Florian Müllner <fmuellner src gnome org>]

commit 741ecfebf00f3caf6712e2e8c6bd2c3f6d68ef91
Author: Joonas Henriksson <joonas henriksson gmail com>
Date:   Sun Nov 24 20:44:47 2019 +0200

    theme: Add :active styling to message-close and media control buttons
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/855

 _common.scss | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/_common.scss b/_common.scss
index cd6eea7..6a82a18 100644
--- a/_common.scss
+++ b/_common.scss
@@ -1155,6 +1155,7 @@ StScrollBar {
           .message-close-button {
             color: lighten($fg_color, 15%);
             &:hover { color: darken($fg_color, 10%); }
+            &:active { color: darken($fg_color, 20%); }
           }
 
           .message-media-control {
@@ -1164,6 +1165,7 @@ StScrollBar {
             &:last-child:ltr { padding-right: 18px; }
             &:last-child:rtl { padding-left: 18px; }
             &:hover { color: darken($fg_color, 10%) }
+            &:active { color: darken($fg_color, 20%); }
             &:insensitive { color: darken($fg_color,40%); }
           }