Update index/search template

internal/templates/index.html

@@ -1,5 +1,5 @@
 {{define "content"}}
-  <article class="container">
+  <div class="container">
     <form action="/search" method="GET">
       <input type="text" id="search" name="q" placeholder="{{ $.SearchPrompt }}">
       <button id="go" type="submit">
@@ -7,5 +7,5 @@
         Go!
       </button>
     </form>
-  </article>
+  </div>
 {{end}}