Update css-conditional-5/Overview.bs

Co-authored-by: Seokho Song <0xdevssh@gmail.com>

Author: meyerweb

css-conditional-5/Overview.bs

@@ -2064,7 +2064,9 @@ for a {{query container}} of the element <var>ele</var>, run these steps:
         else
             &hellip;
     }
-    var cql = Element.matchContainer("(scroll-state(scrollable))");
+    
+    const element = document.getElementById("target");
+    var cql = element.matchContainer("(scroll-state(scrollable))");
     cql.onchange = handleOverflowChange;
     </pre>
 </div>