float双飞布局

  <div class="page-sortable">
    <div class="sortable-item sortable-lf">1</div>
    <div class="sortable-item sortable-mid">2</div>
    <div class="sortable-item sortable-rt">3</div>
  </div>

<style lang="scss" scoped>
.page-sortable {
  height: 80vh;
  margin: 40px auto;
  position: relative;
  clear: both;
  .sortable-item {
    height: 100%;
    float: left;
  }
  .sortable-item.sortable-lf {
    width: 20%;
    background-color: red;
  }
  .sortable-item.sortable-mid {
    width: 50%;
    background-color: green;
  }
  .sortable-item.sortable-rt {
    width: 30%;
    background-color: hotpink;
  }
}
</style>