HighContrast: Add a dark variant

This is just a quick experiment, and so I have another theme with
a dark variant to play with.

gtk/Makefile.am

@@ -1209,6 +1209,9 @@ gtk.gresource.xml: Makefile.am inspector/Makefile.inc
           echo "    <file preprocess='to-pixdata'>theme/Adwaita/assets/$$n</file>" >> $@; \
         done; \
 	echo "    <file alias='theme/HighContrast.css'>theme/HighContrast/gtk.css</file>" >> $@; \
+	echo "    <file alias='theme/HighContrast-dark.css'>theme/HighContrast/gtk-dark.css</file>" >> $@; \
+	echo "    <file>theme/HighContrast/gtk-contained.css</file>" >> $@; \
+	echo "    <file>theme/HighContrast/gtk-contained-dark.css</file>" >> $@; \
 	if test "$(win32_theme)" = "yes"; then \
 	  for f in $(srcdir)/theme/win32/*.css; do \
 	    n=`basename $$f`; \

gtk/theme/HighContrast/_colors.scss

@@ -2,16 +2,16 @@
 // it gets @if ed depending on $variant
 
 
-$base_color: #fff;
-$bg_color: #fff;
-$fg_color: #000;
+$base_color: if($variant == 'light', #fff, #111);
+$bg_color: if($variant == 'light', #fff, #000);
+$fg_color: if($variant == 'light', #000, #fff);
 
 $selected_fg_color: #fff;
-$selected_bg_color: #000; //#4a90d9;
-$selected_borders_color: #000;
+$selected_bg_color: if($variant == 'light', #000, #aaa); //#4a90d9;
+$selected_borders_color: if($variant == 'light', #000, #aaa);
 
 $borders_color: mix($bg_color,$fg_color,50%);
-$borders_edge: #fff;
+$borders_edge: if($variant == 'light', #fff, #000);
 $link_color: $selected_bg_color;
 
 $suggested_color: #4a90d9;
@@ -56,7 +56,6 @@ $backdrop_borders_color: mix($borders_color, $bg_color, 90%);
 @define-color warning_color #{"" + $warning_color};
 @define-color error_color #{"" + $error_color};
 @define-color success_color #{"" + $success_color};
-//@define-color desctructive_color $destructive_color
 
 //WM
 

gtk/theme/HighContrast/gtk-contained-dark.scss

@@ -4,6 +4,8 @@
 //   you need a subtle shade
 // - if you need to inverse a color function use the @if directive to match for dark $variant
 
+$variant: 'dark';
+
 @import 'colors';
 @import 'drawing';
 @import 'common';

gtk/theme/HighContrast/gtk-contained.scss

@@ -0,0 +1,11 @@
+// General guidelines:
+// - very unlikely you want to edit something else than _common.scss
+// - keep the number of defined colors to a minimum, use the color blending functions if
+//   you need a subtle shade
+// - if you need to inverse a color function use the @if directive to match for dark $variant
+
+$variant: 'light';
+
+@import 'colors';
+@import 'drawing';
+@import 'common';

gtk/theme/HighContrast/gtk-dark.css

@@ -0,0 +1 @@
+@import url("resource:///org/gtk/libgtk/theme/HighContrast/gtk-contained-dark.css");