Pen Settings

HTML

CSS

CSS Base

Vendor Prefixing

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Any URLs 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 its URL and the proper URL extension.

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JavaScript

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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Packages

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.

Behavior

Auto Save

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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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HTML

              
                <div class="box bg1">border-box</div>
<div class="box bg2">padding-box</div>
<div class="box bg3">content-box</div>
              
            
!

CSS

              
                .box{
  box-sizing:border-box;
  width:220px;
  height:220px;
  border:12px solid rgba(0,0,0,.5);
  padding:10px;
  background:url(http://www.mrszhao.com/zb_users/upload/codepen/fengjing.jpg) no-repeat center;  /*必须是no-repeat,background-origin才有效*/
  margin-right:10px;
  float:left;
  color:#fff;
}
.bg1{
  background-origin:border-box; /*背景图片从边框开始*/
}
.bg2{
  background-origin:padding-box; /*从内边距开始*/
  background-clip:padding-box;  /*背景图片裁剪在padding内边距范围内*/
}
.bg3{
  background-origin:content-box; /*从内容区开始*/
  background-clip:content-box;/*背景图片裁剪在内容区范围内*/
}

              
            
!

JS

              
                
              
            
!
999px

Console