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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="content">
  <p>Base font size set at 100%, which usually means 16px.
  All text elements below are child elements in the .content div, which is set at 1.5rem, or 24px.
  <p>Try commenting out the .content font-size in the CSS to see how it affects the em-sized fonts.
  <h2 class="em">Headline set at 3em, resulting size 72px</h2>
  <h2 class="rem">Headline set at 3rem, resulting size 48px</h2>
  <p class="em">
    This paragraph is set at 1.5em, resulting font-size is 36px.
  <p class="rem">
    This paragraph is set at 1.5rem, resulting font-size is 24px.
              html {
  font-size: 100%;

.content {
  font-size: 1.5rem;

.em {
  border: 2px solid red;

.rem {
  border: 2px solid blue;

h2.em {
  font-size: 3em;
h2.rem {
  font-size: 3rem;

p.em {
  font-size: 1.5em;

p.rem {
  font-size: 1.5rem;
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