fix: header navigation current link styles (#755)

Author: ricklambrechts

manon/header-navigation-link-focus-variables.scss

@@ -11,6 +11,10 @@
     "header-navigation-link-focus-",
     "navigation-link-focus-"
   );
+  @include link.styling-variables(
+    "header-navigation-current-link-focus-",
+    "header-navigation-link-focus-"
+  );
 
   /* Link focus outline */
   @include outline.outline-variables("header-navigation-link-focus-", initial);

manon/header-navigation-link-focus.scss

@@ -29,8 +29,6 @@ body > header,
 
     a[aria-current="page"],
     a[aria-current="page"]:visited {
-      @extend %header-navigation-current-link-focus-styling;
-
       &:focus {
         @extend %header-navigation-current-link-focus-styling;
         @extend %header-navigation-link-focus-outline;