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

Want to change your Syntax Highlighting theme, Fonts and more?

Visit your global Editor Settings.


  纒色 πŸ‘‰ #father ε…ƒη΄  border 区域
  白色 πŸ‘‰ #father ε…ƒη΄  padding 区域
  黄色 πŸ‘‰ #father ε…ƒη΄  content 区域
  蓝色 πŸ‘‰ #sub ε…ƒη΄ 
<div id="father">
  <div id="sub"></div>


  width 500px
  height @width
  background yellow
  background-clip content-box // η”¨δΊŽεŒΊεˆ† padding 区域
  padding 50px
  border 50px solid red
  position relative
  // box-sizing content-box
  box-sizing border-box
  width 100px
  height @width
  background blue
  position absolute
  left 0%
  top 0%