css吸顶：标题在滚动时会一直贴着最顶上

position: sticky

// css 部分
.container {
    background-color: oldlace;
    height: 200px;
    width: 140px;
    overflow: auto;
  }
  .container div {
    height: 20px;
    background-color: aqua;
    border: 1px solid;
  }
  .container .header {
    position: sticky;
    top: 0;
    background-color: rgb(187, 153, 153);
}

// html 部分
<div class="container">
  <div class="header">Header</div>
  <div>1</div>
  <div>2</div>
  <div>3</div>
</div>