title: Change css based in Select option value selected
body: <p>I have in one form, one selects with one question that if determined value selected I need to display none the next question. How can I make a jquery code that detects that the user selected a determinated option in select and change the CSS of the page?</p>
  
  <pre><code>&lt;select&gt;
     &lt;option value="volvo"&gt;Volvo&lt;/option&gt;
     &lt;option value="saab"&gt;Saab&lt;/option&gt;
     &lt;option value="mercedes"&gt;Mercedes&lt;/option&gt;
     &lt;option value="audi"&gt;Audi&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>