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.


Save Automatically?

If active, Pens will autosave every 30 seconds after being saved once.

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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Visit your global Editor Settings.


      .preview Preview
      .description Description


                html, body
  height: 100%
  width: 100%

  background: #cfcfcf
  display table
  margin 0 auto

  display table-cell
  vertical-align middle
  perspective: 600px

  margin: 0 auto
  width: 200px
  height: 200px

.item:hover .item-inner
  transform: translateX(-100%) rotateY(-180deg)

  width: 100%
  height: 100%
  transition: transform .5s
  transform-style: preserve-3d
  transform-origin: right center

.preview, .description
  text-align: center
  position: absolute
  width: 100%
  height: 100%
  backface-visibility: hidden
  background: whitesmoke
  color: #444
  font: bolder 22px/200px Courier
  border: 3px solid #444;

  background: #ddd

  transform: rotateY( 180deg );