Pen Settings

HTML

CSS

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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JavaScript

Babel includes JSX processing.

Add External Scripts/Pens

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Packages

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Behavior

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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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HTML

              
                <body class="body">
    <div class="box">BOX 區域</div>
</body>
              
            
!

CSS

              
                .body{
  background: #f4f0e6;
}
.box{
  width: 200px;
  height: 200px;
  background: #9dd3a8; /*綠*/
  color:gray;
  display:flex;
  justify-content:center;
  align-items:center;
}
              
            
!

JS

              
                const body = document.querySelector('.body');
const box = document.querySelector('.box');

body.addEventListener('click', function () {
  alert('body');
}, false)

//用參數 e 撈出事件中詳細資訊執行 stopPropagation,當執行完 box 就不會再往外層找到 body 做執行
box.addEventListener('click', function (e) {
  e.stopPropagation();
  alert('box');
}, false)
              
            
!
999px

Console