title: How to use responsive features of bootstrap 2.0
body: <p>I'm using bootstrap 2.0 from twitter and unsure how to make it responsive.</p>
  
  <ul>
  <li>How can I remove elements when in mobile/small screen mode?</li>
  <li>How can I replace elements (i.e replace a big picture with a smaller one)?</li>
  <li>Change a <code>&lt;h2&gt;</code> to be <code>&lt;h5&gt;</code>? etc.</li>
  </ul>