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HTML

CSS

CSS Base

Vendor Prefixing

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JavaScript

Babel includes JSX processing.

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Packages

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Editor Settings

Code Indentation

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HTML

              
                <select name="item" multiple>
  <option value="項目1">項目1</option>
  <option value="項目2">項目2</option>
  <option value="項目3">項目3</option>
  <option value="項目4">項目4</option>
  <option value="項目5">項目5</option>
</select>
              
            
!

CSS

              
                body {
  margin: 50px auto;
  width: 800px;
}

select {
  /* 初期化 */
  appearance: none;
  -moz-appearance: none;
  -webkit-appearance: none;
  border: 2px solid #aaa;
  color: #333;
  font-size: 16px;
  width: 300px;
  background: #fff;
  outline: 0;
  position: relative;
  display: block;
}

select[multiple] option {
  color: #333;
  padding: 5px 5px 5px 35px;
  position: relative;
}

select[multiple] option:checked {
  appearance: none;
  -moz-appearance: none;
  -webkit-appearance: none;
    background: url(https://ginneko-atelier.com/assets/check.svg) 10px center / 15px auto no-repeat!important; 
}
              
            
!

JS

              
                
              
            
!
999px

Console