title: translateZ works but the element scrolls at the same speed as the rest
body: <p>I'm trying to make a parallax effect</p>
  <p>translateZ works because I see the image smaller than it is normally, but when I scroll the page the element scrolls at the same speed as everything else</p>
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-css lang-css prettyprint-override"><code>#parallax {
      width: 100vw;
      height: 100vh;
      background-image: url("https://sitosisti.netlify.app/assets/img/124430694_844262466359332_819877535439111536_n.jpg");
      background-position-x: 30vw;
      background-position-y: 0;
      background-repeat: no-repeat;
      
      background-size: cover;
      transform: translateZ(-2px);
  }
  
  .parallax-container {
      width: 100vw;
      height: 100vh;
      perspective: 1px;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div class="parallax-container"&gt;  
     &lt;div id="parallax"&gt;&lt;/div&gt;
  &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>
  <p>I can't figure out what's not working</p>