refactor(core): updated background for the indicator (#8971)

Author: RitaDias

packages/sanity/src/core/perspective/navbar/PerspectiveLayerIndicator.tsx

@@ -33,7 +33,7 @@ export const GlobalPerspectiveMenuItemIndicator = styled.div<{
         bottom: -var(--indicator-bottom);
         width: var(--indicator-width);
         height: ${$isDraft ? 'calc(var(--indicator-bottom) + 12px)' : 'var(--indicator-bottom)'};
-        background-color: var(--indicator-color);
+        background-color: var(--card-border-color);
       }
     `}
 
@@ -49,7 +49,7 @@ export const GlobalPerspectiveMenuItemIndicator = styled.div<{
           position: absolute;
           left: var(--indicator-left);
           width: var(--indicator-width);
-          background-color: var(--indicator-color);
+          background-color: var(--card-border-color);
         }
 
         &:before {