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HTML Settings

Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <div class="App">
  <h1>Step 3</h1>

  <div class="Example">
    <div>3. setTimeout with delta fix (100ms)</div>
    <div class="Example-position"></div>
    <div class="Box"></div>
              * {
  box-sizing: border-box;

body {
  background: #fdfdfd;
  font-family: Helvetica, Arial, sans-serif;

.App {
  position: relative;
  max-width: 400px;
  margin: 0 auto;
  padding: 40px 20px;

h1 {
  font-size: 1.2em;
  font-weight: bold;
  margin-bottom: 5px;

a {
  color: #409ad7;
  text-decoration: none;
  border-bottom: 1px solid #ddd;
  margin-bottom: 20px;
  display: inline-block;
  &:hover {
    border-bottom-color: #409ad7;

.Example {
  border: 1px solid #ddd;
  border-radius: 3px;
  background: #fff;
  padding: 20px;
  margin-bottom: 10px;

.Example-position {
  margin-top: 5px;
  color: #409ad7;

.Box {
  width: 30px;
  height: 30px;
  background: #34ba9c;
  margin-top: 20px;
  border-radius: 2px;
              const FRAME_DURATION = 1000 / 60; // 60fps frame duration
// If available we are using native "performance" API instead of "Date"
// It it's name suggests it is more performant, read more on MDN:
// https://developer.mozilla.org/en-US/docs/Web/API/Performance
const getTime = typeof performance === 'function' ? performance.now : Date.now;
const MAX_POSITION = 150;

const box = document.querySelector('.Box');
// Initial position
let position = 0;
// Initial time
let lastUpdate = getTime();

function animate() {
  const now = getTime();
  // This is the main part
  // We are checking how much time has passed since the last update
  // and translating that to frames
  const delta = (now - lastUpdate) / FRAME_DURATION;

  // Updating scene logic
  // We want to move the box 1px per each 16.66ms (60fps)
  // so we are multipling 1px with the number of frames passed
  position += 1 * delta;
  // Reset position
  if (position > MAX_POSITION) {
    position -= MAX_POSITION;

  // Render updated scene
  box.style.transform = `translateX(${ position }px)`;

  // Update last updated time
  lastUpdate = now;

  // Fake 10fps using "setTimeout"
  setTimeout(animate, 100);

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