<div class="box">
  <header>
    <h2>双飞翼</h2>
  </header>
  <div class="container">
    <div class="content col">
      <div class="inner">
        content
        <p>来自淘宝UED，玉伯</p>
        <p>1. 首先，left 200，right 150，都浮动</p>
        <p>2. </p>
      </div>
    </div>
    <div class="left col">
      left
    </div>
    <div class="right col">
      right
    </div>
  </div>
</div>
*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

.col{
  float: left;
  
}

.container{
  
}

.content{
  width: 100%;
}

.inner{
  margin: 0 150px 0 200px;
  border: 1px solid red;
}

.left{
  width: 200px;
  margin-left: -100%;
  border: 1px solid red;
}

.right{
  width: 150px;
  margin-left: -150px;
  border: 1px solid red;
}

External CSS

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External JavaScript

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