1、用css实现div的完全居中
.class1{
width: 200px;
height: 200px;
background: red;
position: absolute;
top: 0;
left: 0;
right: 0;
bottom: 0;
margin: auto;
}
.class2{
width: 200px;
height: 200px;
background: yellowgreen;
position: absolute;
left: 50%;
top: 50%;
margin: -100px 0 0 -100px;
}
.class3{
width: 200px;
height: 200px;
background: yellowgreen;
position: absolute;
left: 50%;
top: 50%;
transform:translate(-100px,-100px);
-webkit-transform:translate(-100px,-100px); /*兼容-webkit-引擎浏览器*/
-moz-transform:translate(-100px,-100px); /*兼容-moz-引擎浏览器*/
}
