[gtk/wip/jimmac/emphasize-focus-change] Adwaita: bring more attention to focus change

[Jakub Steiner <jimmac src gnome org>]

commit 7ced506486d629cefc473f9c251f340003c39ce0
Author: Jakub Steiner <jimmac gmail com>
Date:   Thu Apr 30 22:40:21 2020 +0200

    Adwaita: bring more attention to focus change
    
    - as discussed in https://gitlab.gnome.org/GNOME/gtk/-/issues/2644 it's desirable to bring attention to 
what's focused. Instead of pressing `alt` just simply changing focus with `tab` can have a similar effect
    
    Extends https://gitlab.gnome.org/GNOME/gtk/-/merge_requests/1802

 gtk/theme/Adwaita/_drawing.scss | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/gtk/theme/Adwaita/_drawing.scss b/gtk/theme/Adwaita/_drawing.scss
index 7e67786f1a..4bb7d97d5c 100644
--- a/gtk/theme/Adwaita/_drawing.scss
+++ b/gtk/theme/Adwaita/_drawing.scss
@@ -10,11 +10,12 @@
 //
 @mixin focus-ring($target: null, $width: 2px, $offset: -$width, $outer: false) {
   & #{$target} {
-    outline: 0 solid $focus_border_color;
-    outline-offset: if($outer, $offset, $offset + $width);
+    outline: 0 solid transparent;
+    outline-offset: if($outer, $offset + 10px, $offset + $width + 10px);
   }
 
   &:focus:focus-visible #{$target} {
+    outline-color: $focus_border_color;
     outline-width: $width;
     outline-offset: $offset;
   }