docs(site): sticky alert

Author: andreruffert

docs/style.css

@@ -105,6 +105,10 @@
   }
 
   .alert {
+    background-color: light-dark(var(--light-canvas), var(--dark-canvas));
+    position: sticky;
+    top: env(safe-area-inset-top, 0);
+    z-index: 1;
     display: flex;
     flex-direction: column;
     align-items: center;