[libadwaita/wip/snwh/buttons] buttons: redo buttons to use borders, use gtkmix in borders color math

[Sam Hewitt <snwh src gnome org>]

commit bbdc086c6779d2a4d65e23e2a2a47de7e553dcd6
Author: Sam Hewitt <sam snwh org>
Date:   Tue Nov 16 13:50:44 2021 -0330

    buttons: redo buttons to use borders, use gtkmix in borders color math

 src/stylesheet/_colors.scss          | 10 +++++-----
 src/stylesheet/widgets/_buttons.scss | 14 ++++++--------
 2 files changed, 11 insertions(+), 13 deletions(-)
---
diff --git a/src/stylesheet/_colors.scss b/src/stylesheet/_colors.scss
index 6ff2eb86..54e1d9d5 100644
--- a/src/stylesheet/_colors.scss
+++ b/src/stylesheet/_colors.scss
@@ -1,5 +1,5 @@
-$border_opacity: if($contrast == 'high', .5, .15);
-$thin_border_opacity: if($contrast == 'high', .25, .05);
+$border_strength: if($contrast == 'high', 5%, 15%);
+$thin_border_strength: if($contrast == 'high', 25%, 5%);
 $focus_border_opacity: if($contrast == 'high', 0.8, 0.5);
 $window_outline_opacity: if($contrast == 'high', .3, .1);
 
@@ -25,7 +25,7 @@ $view_fg_color: gtkcolor(view_fg_color);
 
 $headerbar_bg_color: gtkcolor(headerbar_bg_color);
 $headerbar_fg_color: gtkcolor(headerbar_fg_color);
-$headerbar_border_color: gtkalpha(gtkcolor(headerbar_border_color), $border_opacity);
+$headerbar_border_color: gtkmix(gtkcolor(headerbar_border_color), $headerbar_bg_color, $border_strength);
 $headerbar_backdrop_color: gtkcolor(headerbar_backdrop_color);
 $headerbar_shade_color: gtkcolor(headerbar_shade_color);
 
@@ -44,8 +44,8 @@ $window_border_backdrop_color: gtkcolor(window_border_backdrop_color);
 
 // Other colors
 
-$border_color: gtkalpha(currentColor, $border_opacity);
-$thin_border_color: gtkalpha(currentColor, $thin_border_opacity);
+$border_color: gtkmix(currentColor, $window_bg_color, $border_strength);
+$thin_border_color: gtkmix(currentColor, $window_bg_color, $thin_border_strength);
 $link_color: $accent_color;
 $link_visited_color: gtkmix($accent_color, $view_fg_color, 80%);
 
diff --git a/src/stylesheet/widgets/_buttons.scss b/src/stylesheet/widgets/_buttons.scss
index 29857124..c55ad9ae 100644
--- a/src/stylesheet/widgets/_buttons.scss
+++ b/src/stylesheet/widgets/_buttons.scss
@@ -1,9 +1,9 @@
 $button_color: gtkalpha(currentColor, .1);
 $button_hover_color: gtkalpha(currentColor, .15);
 $button_active_color: gtkalpha(currentColor, .25);
-$button_checked_color: gtkalpha($window_fg_color, .55);
-$button_checked_hover_color: gtkalpha($window_fg_color, .35);
-$button_checked_active_color: gtkalpha($window_fg_color, .25);
+$button_checked_color: gtkalpha($window_fg_color, .45);
+$button_checked_hover_color: gtkalpha($window_fg_color, .25);
+$button_checked_active_color: gtkalpha($window_fg_color, .15);
 
 $opaque_button_default_bg: gtkmix($window_bg_color, $window_fg_color, 85%);
 
@@ -23,16 +23,16 @@ button {
       background-color: $button_color;
       border-width: 1px;
       border-style: solid;
-      border-color: $button_color;
+      border-color: $border_color;
 
       @if $contrast == 'high' {
         // box-shadow: inset 0 0 0 1px $border_color;
-        border: 1px solid $button_color;
+        border: 1px solid $border_color;
       }
 
       &:hover {
         background-color: $button_hover_color;
-        border-color: $button_hover_color;
+        border-color: gtkmix($border_color, $button_hover_color, 50%);
       }
 
       &.keyboard-activating,
@@ -504,7 +504,6 @@ splitbutton {
   // Reimplementing linked so we don't blow up css
   > button:dir(ltr),
   > menubutton > button:dir(rtl) {
-    border-right-width: 0;
     border-top-right-radius: 0;
     border-bottom-right-radius: 0;
     margin-right: -1px;
@@ -512,7 +511,6 @@ splitbutton {
 
   > button:dir(rtl),
   > menubutton > button:dir(ltr) {
-    border-left-width: 0;
     border-top-left-radius: 0;
     border-bottom-left-radius: 0;
     margin-left: -1px;