fix: deprecation warning global assignments won't be able to declare …

…new variables in future versions

assets/scss/modules/_color_theme.scss

@@ -21,10 +21,11 @@ $themes: (
   ),
 );
 
+$theme-map: ();
+
 @mixin themed() {
   @each $theme, $map in $themes {
     .theme--#{$theme} & {
-      $theme-map: () !global;
       @each $key, $submap in $map {
         $value: map-get(map-get($themes, $theme), '#{$key}');
         $theme-map: map-merge(
@@ -35,7 +36,7 @@ $themes: (
         ) !global;
       }
       @content;
-      $theme-map: null !global;
+      $theme-map: ();
     }
   }
 }