title: CSS: can change height by px, but not by %
body: <p>I am trying to edit the CSS of my Wordpress theme. </p>
  
  <p>I have an element whose height I can successfully change from within Element Inspector, if I specify a certain pixel height, for example:</p>
  
  <pre><code>height=100px; 
  </code></pre>
  
  <p>But when I try to change the height by specifying a percentage, for example:</p>
  
  <pre><code>height=50%; 
  </code></pre>
  
  <p>The element does not change height. Any thoughts on what I'm doing wrong, or how to troubleshoot? </p>
  
  <p>None of the parent elements appear to have any height properties.</p>