[libadwaita/wip/exalm/button-fix] stylesheet: Fix .osd button states

[Alexander Mikhaylenko <alexm src gnome org>]

commit 4a59554d066eec073531d367a986d0838682d893
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Wed Sep 15 13:25:26 2021 +0500

    stylesheet: Fix .osd button states
    
    Since we changed osd to use transparent black, it has become completely
    invisible on black bg, which is not uncommon on e.g. image viewers.
    
    Change background color for hover/etc instead of opacity to mitigate that.

 src/stylesheet/widgets/_buttons.scss | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
---
diff --git a/src/stylesheet/widgets/_buttons.scss b/src/stylesheet/widgets/_buttons.scss
index 99b81f07..dd6c06db 100644
--- a/src/stylesheet/widgets/_buttons.scss
+++ b/src/stylesheet/widgets/_buttons.scss
@@ -117,25 +117,25 @@ button {
 
     &:hover {
       color: white;
-      background-color: transparentize(black, .5);
+      background-color: gtkalpha(gtkmix(black, currentColor, 85%), .65);
     }
 
     &.keyboard-activating,
     &:active {
       color: white;
-      background-color: transparentize(black, .2);
+      background-color: gtkalpha(gtkmix(black, currentColor, 75%), .65);
     }
 
     &:checked {
-      background-color: transparentize(black, .25);
+      background-color: gtkalpha(gtkmix(black, currentColor, 8%), .65);
 
       &:hover {
-        background-color: transparentize(black, .35);
+        background-color: gtkalpha(gtkmix(black, currentColor, 75%), .65);
       }
 
       &.keyboard-activating,
       &:active {
-        background-color: transparentize(black, .1);
+        background-color: gtkalpha(gtkmix(black, currentColor, 65%), .65);
       }
     }