title: `content: ''` vs `content: none`
body: <p>I was reading through Eric Meyer's CSS reset and saw this:</p>
  
  <pre><code>blockquote:before, blockquote:after,
  q:before, q:after {
      /* ? */ content: '';
      /* ? */ content: none;
  }
  </code></pre>
  
  <p>I assume that some browsers support <code>content: ''</code> and some <code>content: none</code>, is this the case? And which browsers support which?</p>