Update SCSS color variable to CSS custom property

Update SCSS color variable to CSS custom property

diff --git a/assets/stylesheets/common/discourse-policy.scss b/assets/stylesheets/common/discourse-policy.scss
index fcc3d16..a49a1fb 100644
--- a/assets/stylesheets/common/discourse-policy.scss
+++ b/assets/stylesheets/common/discourse-policy.scss
@@ -75,7 +75,7 @@
     padding: 0.5em;
 
     &:hover {
-      color: $primary-very-low;
+      color: var(--primary-very-low, $primary-very-low);
       background: var(--primary-medium, $primary-medium);
     }
   }

GitHub sha: 08a16fb3