fix(scrollable-container): put shadows on top of content

Author: abelflopes

packages/components/_provisional/src/scrollable-container/index.module.scss

@@ -26,6 +26,7 @@
     width: 100%;
     transform: translate(var(--scroll-x), var(--scroll-y));
     pointer-events: none;
+    z-index: 1;
 
     &::before,
     &::after {
@@ -41,6 +42,7 @@
     width: 100%;
     transform: translate(var(--scroll-x), var(--scroll-y));
     pointer-events: none;
+    z-index: 1;
   }
 
   // shadow top