title: resize the content property's image
body: <p>I have an unordered list of links and each link has a unique id.<br>
  I'm using that id with the <code>:before</code> selector to place<br>
  the associated website's favicon before the link (using the content property).<br>
  One of these icons is twice the size of the others.<br>
  Is there any way to change the size of this icon using CSS?<br>
  If the answer is no, is there any way to do this other than editing the image?</p>
  
  <p>Visual reference:</p>
  
  <p><img src="https://i.stack.imgur.com/Eogud.jpg" alt="enter image description here"></p>
  
  <p>Here is what I tried (and it doesn't seem to work):</p>
  
  <pre><code>#geog:before
  {
      content: url("icons/geogebra.ico") " ";
      height: 50%;
      width: 50%;
  }
  </code></pre>