title: jQuery get height in pixels
body: <p>I have the following elements in a HTML page:</p>
  
  <pre><code>&lt;body&gt;
      &lt;div style="height:100%; width:100%"&gt;
      &lt;div style="height:100px;"&gt;&lt;/div&gt;
      &lt;div id="container" style="height:25%; width:50%"&gt;
      &lt;/div&gt;
  </code></pre>
  
  <p>Now I would like to get the height in pixels of the div <code>container</code> using jQuery (or plain JavaScript).
  How can I do it?</p>
  
  <pre><code>$('#container').height() // returns `0`
  </code></pre>