title: Can I set cross-axis size of a flex box item to a percentage of container?
body: <p>I have three elements aligned horizontally in a flex box of set width and I would like the flex box to take the cross-axis size (height) of the largest of two of them and for the third to take 80% of that size. Is this possible?</p>
  
  <p><a href="https://codepen.io/anfedorov/pen/dRoexw?editors=1100" rel="nofollow noreferrer">Code pen here</a>.</p>
  
  <pre><code>^ code
  </code></pre>