title: CSS: Setting height relative to current height of parent element
body: <p>So my question is basicly stated in the topic.
  Why can't I just say:</p>
  <pre><code>&lt;div style=&quot;min-height: 100vh&quot;&gt;
      &lt;div style=&quot;height: 100%&quot;&gt;
      &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  <p>If I do this, the second div does not scale to 100% of the first one.</p>