title: Two Pane Website - Stretching Vertical Height?
body: <p>I have this layout:</p>
  
  <p><img src="https://i.stack.imgur.com/Q62NR.png" alt=""></p>
  
  <p>The topbar is fixed. Then I want to have a sidebar in the left pane, and a right pane with the main content. The panes are different colors, and seperated by a border.</p>
  
  <p>The problem is that sometimes the left pane will be taller and sometimes the right pane will be taller. And so one pane is shorter than the other (the color ends and you see white).</p>
  
  <p>I've tried <code>height:100%;</code> but that only works if the content is shorter than the browser height.</p>
  
  <p>How can I solve this with just CSS?</p>