Pen Settings



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. You can use the CSS from another Pen by using it's URL and the proper URL extention.

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Babel includes JSX processing.

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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Add Packages

Search for and use JavaScript packages from npm here. By selecting a package, an import statement will be added to the top of the JavaScript editor for this package.


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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.

Format on Save

If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.

Editor Settings

Code Indentation

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      <p>Lorem ipsum dolor sit amet, consectetursd adipisicing elit. Est necessitatibus commodi illum ullam quod vel in rerum repellat, velit voluptas doloribus veritatis, quae optio sint magni sunt id itaque quia?</p>


                * {
  box-sizing: border-box;

main {
  width: 100%;
  aspect-ratio: 1/1;
  border: thin solid red;
  min-height: 0;

/* vertical writing mode (could also be on the container itself) */
div {
  height: 100%;
  writing-mode: vertical-rl;

section {
  height: 100%;
  contain: inline-size;
  border: thick solid blue;

/* 💥 changes to content impact the container's inline size */
/* the results currently seem to be stateful? */
p {
  letter-spacing: 1em;
  line-height: 2;