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图片，盒模型水平居中

盒模型水平居中

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <style type="text/css">
        * {
            margin: 0;
            padding: 0;
        }

        #wrap {
             500px;
            height: 500px;
            background: grey;
            position: relative;
        }
        #box{
            position: absolute;
            top: 0;
            left: 0;
            bottom: 0;
            right: 0;
            margin: auto;
             200px;
            height: 200px;
            background: deeppink;
        }
    </style>
</head>
<body>
<div id="wrap">
    <div id="box"></div>
</div>
</body>
<script type="text/javascript">
    window.onload = function () {
        var box = document.getElementById('box');
    }
</script>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <style type="text/css">
        * {
            margin: 0;
            padding: 0;
        }

        #wrap {
             500px;
            height: 500px;
            background: grey;
            position: relative;
        }
        #box{
            position: absolute;
            top: 50%;
            left: 50%;
            margin-top: -100px;
            margin-left: -100px;
             200px;
            height: 200px;
            background: deeppink;
        }
    </style>
</head>
<body>
<div id="wrap">
    <div id="box"></div>
</div>
</body>
<script type="text/javascript">
    window.onload = function () {
        var box = document.getElementById('box');
    }
</script>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <style type="text/css">
        * {
            margin: 0;
            padding: 0;
        }

        #wrap {
             500px;
            height: 500px;
            background: grey;
            position: relative;
        }
        #box{
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%,-50%);
             200px;
            height: 200px;
            background: deeppink;
        }
    </style>
</head>
<body>
<div id="wrap">
    <div id="box"></div>
</div>
</body>
<script type="text/javascript">
    window.onload = function () {
        var box = document.getElementById('box');
    }
</script>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <style type="text/css">
        * {
            margin: 0;
            padding: 0;
        }

        #wrap {
             500px;
            height: 500px;
            background: grey;
            display: flex;
            justify-content: center;
            align-items: center;
        }
        #box{
             200px;
            height: 200px;
            background: deeppink;
        }
    </style>
</head>
<body>
<div id="wrap">
    <div id="box"></div>
</div>
</body>
<script type="text/javascript">
    window.onload = function () {
        var box = document.getElementById('box');
    }
</script>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <style type="text/css">
        * {
            margin: 0;
            padding: 0;
        }

        #wrap {
             500px;
            height: 500px;
            background: grey;
            display: -webkit-box;
            -webkit-box-pack: center;
            -webkit-box-align: center;
        }
        #box{
             200px;
            height: 200px;
            background: deeppink;
        }
    </style>
</head>
<body>
<div id="wrap">
    <div id="box"></div>
</div>
</body>
<script type="text/javascript">
    window.onload = function () {
        var box = document.getElementById('box');
    }
</script>
</html>

图片水平居中：

//利用伪元素
<style>
    * {
        margin: 0;
        padding: 0;
    }
    html,body{
        height: 100%;
    }
    body{
        text-align: center;
    }
    body::after{
        content: "";
        display: inline-block;
        height: 100%;
        vertical-align: middle;
    }
    img{
        vertical-align: middle;
    }

</style>
</head>
<body>
    <img src="https://placehold.it/200x200">
</body>

查看全文

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原文地址：https://www.cnblogs.com/zzxuan/p/9613286.html