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CSS Base

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Add External Stylesheets/Pens

Any URL's added here will be added as <link>s in order, and before the CSS in the editor. If you link to another Pen, it will include the CSS from that Pen. If the preprocessor matches, it will attempt to combine them before processing.

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Add External Scripts/Pens

Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

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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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Code Indentation


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Auto-Updating Preview

If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.

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.

              <section class="section">

<p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. Donec odio. Quisque volutpat mattis eros. Nullam malesuada erat ut turpis. Suspendisse urna nibh, viverra non, semper suscipit, posuere a, pede.</p>

<p>Donec nec justo eget felis facilisis fermentum. Aliquam porttitor mauris sit amet orci. Aenean dignissim pellentesque felis.</p>

  <button class="fancy">Click Me, Click Me!<span class="rejection">Dang it!</span></button>
<p>Morbi in sem quis dui placerat ornare. Pellentesque odio nisi, euismod in, pharetra a, ultricies in, diam. Sed arcu. Cras consequat.</p>

<p>Praesent dapibus, neque id cursus faucibus, tortor neque egestas auguae, eu vulputate magna eros eu erat. Aliquam erat volutpat. Nam dui mi, tincidunt quis, accumsan porttitor, facilisis luctus, metus.</p>

<p>Phasellus ultrices nulla quis nibh. Quisque a lectus. Donec consectetuer ligula vulputate sem tristique cursus. Nam nulla quam, gravida non, commodo a, sodales sit amet, nisi.</p>
              section {
  margin: 2rem auto;
  text-align: left;
  width: 25rem;

.fancy {
  background: rgb(255, 255, 255);
  border: 2px solid rgb(0, 0, 0);
  border-radius: 4px;
  color: rgb(0, 0, 0);
  display: block;
  font-weight: bold;
  margin: 1rem auto;
  padding: 1.2rem 1rem 0 1rem;
  transition: background-color 3000ms ease-in-out;
  // transition: color 500ms ease-in-out;
  .rejection {
    color: rgb(255, 255, 255);
    display: block;
  &:hover {
    background: rgb(0, 0, 0);
    color: rgb(255, 255, 255);
    transition: background-color 200ms ease-in-out, color 200ms, ease-in-out;
    .rejection {
      color: rgb(0, 0, 0);
      transition: color 0s ease-in-out;

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