title: How to change css of tag from an outside link
body: <p>I have a menu in a tag called <code>sf-menu</code>.</p>
  
  <p>I need the visibility to change to <code>none</code> when the link is clicked and toggled back when clicked again.</p>
  
  <p>Can I achieve this with CSS only or do I need JavaScript?</p>
  
  <p>Hoping someone can help me with an example.</p>
  
  <pre><code>.sf-menu {visibility: visible}
  &lt;a class="closed" href="#sidewidgetarea"&gt; Switch&lt;/a&gt;
  </code></pre>