`order`属性定义项目的排列顺序。数值越小，排列越靠前，默认为0。 ~~~css .item { order: <integer>; } ~~~  ~~~html <div class="box"> <div class="box-item">1</div> <div class="box-item">2</div> <div class="box-item">3</div> <div class="box-item order">4<div>(order:-1)</div></div> </div> ~~~ ~~~css .box { display: flex; background-color: white; } .box-item { width: 200px; height: 200px; line-height: 200px; vertical-align: middle; margin: 5px; background-color: #ffd200; font-size: 100px; color: white; text-align: center; } .box-item div { font-size: 14px; position: relative; top: -150px; } .order { order: -1; } ~~~