title: css background image not showing up
body: <p>I can't figure out why this background image does not show up.  It seems like the image is getting sent to the browser, and that the css rule is getting applied.</p>
  
  <p>When I inspect element I get these matched rules.  When I click on the 'images/o.png' link it shows me the expected image
      .player1_move {
        width: 30px;
        height: 30px;
        background-image: url('images/o.png');
      }</p>
  
  <p>----------- below is the css and html that I have ---------</p>
  
  <pre><code>  .player1_move {
      width: 30px;
      height: 30px;
      background-image: url('images/o.png');
    }
  
   &lt;table&gt;
    &lt;tr&gt;
      &lt;td id = "0-0" class="player1_move"&gt;&lt;/td&gt;
    &lt;/tr&gt;
   &lt;/table&gt;
  </code></pre>