<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>元素水平垂直居中</title>
<style>
/*方式一*/
.box{
width: 100px;
height: 100px;
background: red;
position: absolute;
top: 50%;
left: 50%;
margin-left: -50px;
margin-top: -50px;
}
/*方式二*/
.box{
width: 100px;
height: 100px;
background: red;
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50px,-50px);
/*或者transform: translate(-50%,-50%);*/
}
/*方式三 技巧*/
.box{
width: 100px;
height: 100px;
background: red;
position: absolute;
top: 0;
left: 0;
right: 0;
bottom: 0;
margin:auto;
}
/*方式四 弹性盒*/
.father{
display: flex;
width: 400px;
height: 400px;
background: red;
justify-content: center;
align-items: center;
}
.son{
width: 100px;
height: 100px;
background: aqua;
}
</style>
</head>
<body>
<div class="box">我需要用多种方式居中你</div>
<div class="father">
<div class="son"></div>
</div>
</body>
</html>
来源：https://www.cnblogs.com/lhl66/p/8724939.html