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Use npm Packages

We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

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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='box'>
  <h1 class='heading'>The ringing in my ears is from another life.</h1>
<div class='box'>
   <h2 class='[  heading  heading--2  ]'>The world is quiet here.</h2>
<blockquote class='[  box  box--wide  ]'>
   <p class='[  heading  heading--3  ]'>I believe every material has a grain, including the web. But this assumption flies in the face of our expectations for technology. Too often, the internet is cast as a wide-open, infinitely malleable material.</p>
    &mdash;<cite><a href=''>Frank Chimero</a></cite>
              /* Demo page styling: */

body {
  padding: 4rem;

.box {
  padding: 2rem;
  max-width: 14rem;
  background-color: #f2f2f2;

.box--wide {
  max-width: 50rem;

* {
  margin: 0;
  padding: 0;

* + * {
  margin-top: 2rem;

/* The good stuff: */

:root {
  /* The intrinsic width of the underline stroke (in pixels). This is 
   * the same as the height of the cap images. Don't specify the
   * units! This is because of some of the calculations we do later on. */
  --underline-intrinsic-width: 8;
  /* The actual width of the underline stroke we want to render (in pixels).
   * You can modify this, and the sizing and positioning should be calculated
   * accordingly. Again, Don't specify the units! */
  --underline-width: 12;
  /* The colour used to draw the underline. It should match the colour
   * used in the cap images... unfortunately we can't modify the SVG
   * fill via CSS because it's a background image. */
  --underline-color: #f1a1e3;
  /* We need to know the width of the cap images so that we
   * can position everything on the x axis accordingly. */
  --underline-cap-width: 4px;
  /* The border is positioned relative to the bottom of the line.
   * We can move it upwards a little to create an overlap effect. */
  --underline-offset-y: -2px;
  /* The padding to add to the x axis. By default, the caps would be
   * aligned with the beginning and end of the line. */
  --underline-padding-x: 0.12em;
  /* The cap images to use that form the left and right rounded
   * shape. I guess these could be any shape, they don't
   * necessarily have to be round 🙂.
  --cap-image-left: url(;
  --cap-image-right: url(;
.heading {
  display: inline;
  --underline-width-scale: calc(var(--underline-width) / var(--underline-intrinsic-width));
  padding: 0 calc(var(--underline-padding-x) + calc(var(--underline-cap-width) * var(--underline-width-scale)));
  box-decoration-break: clone;
  background-repeat: no-repeat;
  color: #1221ff;
    linear-gradient(180deg, var(--underline-color), var(--underline-color)),
    calc(var(--underline-cap-width) * var(--underline-width-scale)),
  background-position-y: calc(100% - var(--underline-offset-y) * -1);
    calc(100% - calc(var(--underline-cap-width) * var(--underline-width-scale) * 2)) calc(var(--underline-width) * 1px),
    auto calc(var(--underline-width) * 1px),
    auto calc(var(--underline-width) * 1px);

.heading--2 {
  --underline-width: 8;
  --underline-offset-y: -2px;

.heading--3 {
  font-size: 3rem;
  font-weight: bold;
  --underline-width: 20;
  --underline-offset-y: -2px;
  --cap-image-left: url(;
  --cap-image-right: url(;

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