css绝对居中 

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
      .box{
        width:400px;
        height: 400px;
        background: yellow;
        position: absolute;
      }
      .center-item{
        background: red;
        width: 50px;
        height: 50px;
        position: absolute;
        left: 50%;
        top: 50%;
        transform: translate(-50%,-50%);
      ;
      }
      .box1{
        left: 420px;
        width:400px;
        height: 400px;
        background: green;
        position: relative;
      }
      .center-item1{
        background: blueviolet;
        width: 50px;
        height: 50px;
        position: absolute;
        left: 0;
        top: 0;
        right: 0;
        bottom: 0;
        margin: auto;
      }
      .box2{
        top: 8px;
        left: 840px;
        width:400px;
        height: 400px;
        background: cornflowerblue;
        text-align: center;
        position: absolute;
      }
      .box2 i{
        display: inline-block;
        vertical-align: middle;
        height: 100%;
      }
      .center-item2{
        background: purple;
        width: 50px;
        height: 50px;
        display: inline-block;
        vertical-align: middle;
      }
      .box3{
        left: 0;
        top: 20px;
        width:400px;
        height: 400px;
        background:indianred;
        position: relative;
        display: flex;
        align-items: center;/*垂直居中*/
      }
      .center-item3{
        background: greenyellow;
        width: 50px;
        height: 50px;
        margin: 0 auto;
      }
    </style>
  </head>
  <body>
    <div class="box">
      <div class="center-item">

      </div>
    </div>
    <div class="box1">
      <div class="center-item1">

      </div>
    </div>
    <div class="box2">
      <i></i>
      <div class="center-item2">

      </div>
    </div>
    <div class="box3">
      <div class="center-item3">

      </div>
    </div>
  </body>
</html>

 

posted @ 2019-01-15 11:55  Frank-f  阅读(93)  评论(0)    收藏  举报