title: jQuery animate background position
body: <p>I can't seem to get this working.</p>
  
  <pre><code>$('#product_family_options_dd').animate({
    height: '300px',
    width: '900px',
    backgroundPosition: '-20px 0px',          
  },
  </code></pre>
  
  <p>The height and width animate but not the background.</p>