title: background-size: cover not working?
body: <p>This is my page <a href="http://inogroup.it/preload/index.htm" rel="noreferrer">http://inogroup.it/preload/index.htm</a></p>
  
  <p>Width of image boxes is responsive</p>
  
  <p>How to set the height to be responsive too? Like 50% of the screen?</p>
  
  <p>If I do this change: </p>
  
  <pre><code>.pattern{
      background-size: contain;
      margin-bottom:25px;
      width:100%;
      height:50%; 
  }
  </code></pre>
  
  <p>it's not working</p>
  
  <p>Thank you very much!</p>