title: Accordion icons not appear
body: <p>Can anyone tell me what is wrong with this code? There is no + icon appear.</p>
  
  <p>What do I have:</p>
  
  <p><strong>JS (jQuery):</strong></p>
  
  <pre><code>&lt;script&gt;
    $(document).ready(function() {
      $(function() {
        $("#accordion").accordion({
          icons: icons,
          collapsible: true,
          active: false,
          heightStyle: "content"
        });
        var icons = {
          header: "ui-icon-circle-plus",
          activeHeader: "ui-icon-circle-minus"
        };
  
      });
    });
  &lt;/script&gt;
  </code></pre>
  
  <p><strong>CSS:</strong></p>
  
  <pre><code>.ui-icon-circle-plus {
      background-color:red;
      background-size:20px;
      width:20px;
      height:20px;
  }
  </code></pre>