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  (async function() {
    if (CSS["paintWorklet"] === undefined)
      await import(
        "[email protected]/dist/css-paint-polyfill.js"
      "[email protected]/curved-line.js"
    The future of CSS is getting exciting with the arrival of
    <strong>CSS Houdini</strong>. Using its <strong>Paint API</strong>, we can create our
    custom style implementation.
  <hr />
  <p>The browser supports for <strong>Paint API</strong> is also
    getting better, and with a polyfill, we can support out more browsers.
    <strong>CurvedLine (curved-line)</strong> is a CSS Houdini implementation to create a custom horizontal line.
  <h2>You can customize it!</h2>
    With the help of CSS properties, you can change the shape of the horizontal line.
  <p>For example, you can make it dark blue, and more curved:</p>
  <hr class="custom-line-1" />
  <p>or, you reduced the curved size, make it to bright pink, and shorten the interval:</p>
  <hr class="custom-line-2" />
  <p>or, you can also shorten more the interval to make a diffferent feel with the line:</p>
  <hr class="custom-line-3" />
  <p>Further reading:</p>
    <li><a href="">See this demo on Codepen</a></li>
    <li><a href="">See more examples on Codepen</a></li>
    <li><a href="">CurvedLine Github repository</a></li>
    <li><a href="">See more information about CSS Houdini</a></li>


                main {
  max-width: 500px;
  margin: 30px auto;
  color: #152831;
  font-family: "Graphik", "Helvetica Neue", helvetica, "Apple Color Emoji",
    arial, sans-serif;
  font-size: 14px;
hr {
  height: 20px;
  border: 0;
  background: paint(curved-line);
.custom-line-1 {
  --curved-lineHeight: 30; /* default: element height */
  --curved-lineWidth: 5; /* default: 3 */
  --curved-lineColor: midnightblue; /* default: 'black' */
  --curved-lineSpread: 20; /* default: 50 */
  height: 50px;
.custom-line-2 {
  --curved-lineHeight: 5; /* default: element height */
  --curved-lineWidth: 2; /* default: 3 */
  --curved-lineColor: deeppink; /* default: 'black' */
  --curved-lineSpread: 10; /* default: 50 */
  height: 10px;
.custom-line-3 {
  --curved-lineHeight: 5; /* default: element height */
  --curved-lineWidth: 5; /* default: 3 */
  --curved-lineColor: saddlebrown; /* default: 'black' */
  --curved-lineSpread: 2; /* default: 50 */
  height: 10px;