lass="prettyprint linenums">
&lt;button class="btn btn-danger" data-toggle="collapse" data-target="#demo"&gt;
  simple collapsible
&lt;/button&gt;

&lt;div id="demo" class="collapse in"&gt; … &lt;/div&gt;</pre>
          <div class="alert alert-info">
            <strong>Heads up!</strong>
            To add accordion-like group management to a collapsible control, add the data attribute <code>data-parent="#selector"</code>. Refer to the demo to see this in action.
          </div>
          <h3>Methods</