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CSS Base

Vendor Prefixing

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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You're using npm packages, so we've auto-selected Babel for you here, which we require to process imports and make it all work. If you need to use a different JavaScript preprocessor, remove the packages in the npm tab.

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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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.

              <main id="main" style="--color: red">
  <article id="article-1">
      Lorem ipsum dolor, sit amet consectetur adipisicing elit. Repellat error sunt quos quam dignissimos asperiores voluptatibus ab deserunt, quidem doloribus vitae repellendus? Unde dolorem debitis quod aut molestias aliquid esse!
  Inheritance means
  The DOM-proximity of a property definition
  matters more than the specificity of the selectors used
p {
  --color: darkgreen;
  color: var(--color);

#article-1 {
  --color: orange;

#main {
  /* see inline style… */

  Specificity only resolves conflicts
  when the property is being defined multiple times
  on a single DOM element (eg the `p` tag).
  DOM-proximity is ignored when determining specificity.
p {
  --bg: lightgreen;
  background: var(--bg);

#article-1 p {
  --bg: yellow;

#main p {
  --bg: pink;

/* style */
* { box-sizing: border-box;}
body {
  align-content: center;
  display: grid;
  justify-content: center;
  min-height: 100vh;
  padding: 1em;
p {
  padding: 1em;
  max-width: 30em;
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