title: CSS minmax invalid property value
body: <p>I want to set the <code>minmax</code> property for my <code>grid-template-columns</code>. But for some reason I don't get it to work.</p>
  
  <p>Here's my code:</p>
  
  <pre><code>.start {
      width: 100%;
      display: grid;
      grid-template-columns: minmax(320px, 1fr) minmax(320px, 1fr);
      grid-template-rows: auto;
      grid-gap: 2%;
  }
  
  &lt;div class="start"&gt;
    &lt;div class="news"&gt;&lt;/div&gt;
    &lt;div class="video"&gt;&lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>When I inspect the <code>.start</code> class in Chrome, it just says "invalid property value" for the <code>minmax</code> attribute.</p>
  
  <p>I just want a two-column layout which becomes a one-column layout when the viewport gets to narrow.</p>