title: Center content vertically in Twitter Bootstrap Grid system
body: <p>I do not find a way to center content vertically in Twitter Bootstrap Grid system. <a href="http://twitter.github.com/bootstrap/scaffolding.html#gridSystem" rel="nofollow">http://twitter.github.com/bootstrap/scaffolding.html#gridSystem</a></p>
  
  <p>For example</p>
  
  <pre><code>&lt;div class="row"&gt;
    &lt;div class="span4" style="height:50px;min-height: 50px;"&gt;My centered object vertically&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>The object in span4 div will always be at the top of div. I have tried to put <code>vertical-align: middle;</code> on parent and child Div's but that do not help.</p>