<h3>flex</h3>

<div class="container">
  <div class="left">我是左边</div>
  <div class="right">我是右边</div>
</div>
.container {
  width: 100%;
  height: 200px;
  display: flex;
  background-color: #e1e1e1;
}

.left {
  width: 100px;
  background-color: pink;
}

.right {
  flex: 1;
  /* flex: 1 1 auto;的简写形式。表示有剩余空间就放大，空间不足会缩小 不设固定大小和比例   */
  background-color: yellow;
}

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