title: Why cannot change checkbox color whatever I do?
body: <p>I try to style checkbox background color, but it won't change whatever I do. I am using firefox 29 latest.</p>
  
  <p>Is there some rule changes in css or may be in the browser?</p>
  
  <p><strong>CSS:</strong></p>
  
  <pre><code>input[type="checkbox"] {
      background: #990000;    
  }
  
  .chk {
     background-color: #990000;  
  
  }
  </code></pre>
  
  <p>Here is a demo <a href="http://jsfiddle.net/6KXRg/" rel="noreferrer">http://jsfiddle.net/6KXRg/</a></p>