Adwaita: Theme calendar day names differently

Just to show how its done. This will need some tweaks.

gtk/theme/Adwaita/_common.scss

@@ -2747,8 +2747,11 @@ GtkCalendar {
     }
   }
 
-  &:inconsistent, &:inconsistent:backdrop,
-  &.highlight, &.highlight:backdrop { color: gtkalpha(currentColor, 0.55); }
+  &:inconsistent, &:inconsistent:backdrop { color: gtkalpha(currentColor, 0.55); }
+  &.highlight, &.highlight:backdrop {
+    color: $fg_color;
+    background: $borders_color;
+  }
 
 
   &:backdrop {

gtk/theme/Adwaita/gtk-contained-dark.css

@@ -3685,8 +3685,11 @@ GtkCalendar {
     GtkCalendar.button:insensitive, .header-bar GtkCalendar.button.titlebutton:insensitive,
     .titlebar GtkCalendar.button.titlebutton:insensitive {
       color: rgba(147, 150, 149, 0.45); }
-  GtkCalendar:inconsistent, GtkCalendar:inconsistent:backdrop, GtkCalendar.highlight, GtkCalendar.highlight:backdrop {
+  GtkCalendar:inconsistent, GtkCalendar:inconsistent:backdrop {
     color: alpha(currentColor,0.55); }
+  GtkCalendar.highlight, GtkCalendar.highlight:backdrop {
+    color: #eeeeec;
+    background: #1c1f1f; }
   GtkCalendar:backdrop {
     color: #d4d4d4;
     border-color: #1e2222; }