from right to left as soon as the page loads.
  </p>
  <div id="animation-box">Filler Text</div>
</body>
<script>
  await sleep(0.2);
  let animationBox = document.getElementById('animation-box');
  expect(animationBox.offsetLeft < 150 && animationBox.offsetLeft > 120).toBe(true, `animation start should be on the right: ${animationBox.offsetLeft}`);
  await sleep(1);
  expect(animationBox.offsetLeft > 35 && animationBox.offsetLeft < 75).toBe(true, `animation should be in the middle: ${animationBox.offsetLef