Fix override css

Fixes #9405

docs/overrides/main.html

@@ -4,14 +4,14 @@
   <style>
 
     /* Preserve link color */
-    .md-typeset a,
-    .md-typeset a:focus,
-    .md-typeset a:hover {
+    .md-announce a,
+    .md-announce a:focus,
+    .md-announce a:hover {
       color: white;
       text-decoration: underline;
     }
 
-    .md-typeset .announce h2 {
+    .md-announce h2 {
       display: block;
       font-size: 1.5em;
       margin-block-start: 0.83em;
@@ -27,11 +27,9 @@
       white-space: nowrap;
     }
   </style>
-<div id="announce">
   <div><h2>Black lives matter.</h2></div>
   We stand in solidarity with the Black community.<br/>
   Racism is unacceptable.<br/>
   It conflicts with <a href="https://git.k8s.io/community/values.md">the core values of the Kubernetes project</a> and our community does not tolerate it.
   <p></p>
-</div>
 {% endblock %}