Pen Settings



CSS Base

Vendor Prefixing

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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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Visit your global Editor Settings.


                <div class="img">
  <div class='mask'></div>


  width 700px
  height @width
  background url("") center/cover
  position absolute
  overflow hidden
    background-image none
    filter drop-shadow(3px 3px 5px black)
    z-index 100
      content ''
      width 100%
      height 100%
      background @background
      display block
      filter blur(4px) 
      clip-path polygon(0% 0%, 0% 100%, 25% 100%, 25% 25%, 75% 25%, 75% 75%, 25% 75%, 25% 100%, 100% 100%, 100% 0%)
// 背景色
  width 100vw
  height 100vh
  background #1d1e22
  display flex
  justify-content center
  align-items center