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. 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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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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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.


.box.half width: 50%
.box.full-50vw width: calc(100vw - 50%)
  span width: 50vw
  .box.w10em(style="margin-left: 0") width: 10em
  .box.intend-10em(style="margin-right: 0") width: calc( 100% - 10em )
    span.left.w1em X
    span.right.w1em X
    | 1em indent box
    | width: calc(100% - 2em)
  | width: calc((10vmax - 10vmin) * 2)
  | height: calc(10vmax - 10vmin)


  box-sizing: border-box

html, body
  margin: 0
  padding-bottom: 5em
  display: inline
  display: inline-block
  text-align: center
  text-align: left
  text-align: right

  float: left
  float: right
  display: block
  clear: both
  content: ""

  background: #ccc
  margin: 0 auto
  padding: .25em 
  text-align: center
  white-space: nowrap
  min-width: 1em
  min-height: 1em
  padding: 0
  background: transparent
  border: 2px solid #e93d29
  width: 50vw
  background: #f6cd4c
  width: 50%
  background: #fa8ead
  width: calc( 100% - 50vw )
  background: #fe7407
  width: 10em
  background: #a0dbe3
  width: calc( 100% - 10em )
  background: #6fb8a4
  width: calc( 100% - 2em )
  text-align: center
  width: 1em
  background: #a4cad1
  width: calc((10vmax - 10vmin) * 2)
  height calc(10vmax - 10vmin)