垂直居中css

第一种方法 使用display: table;来实现垂直居中

<div style="text-align: center;  500px;height:200px; display: table;border: green solid 1px;">
    <span style="display: table-cell; vertical-align: middle; "><img alt="" src="https://www.baidu.com/img/baidu_jgylogo3.gif" style="display: inline-block;" /></span>
</div>

第二种方法 使用绝对定位来实现垂直居中

<div style=" 500px;height:200px; position: relative; border: green solid 1px;">
    <img alt="" src="https://www.baidu.com/img/baidu_jgylogo3.gif" style=" 120px; height: 40px;position: absolute; left:50%; top: 50%; margin-left: -60px;margin-top: -20px;" />
</div>

第三种方法 使用flex布局来实现垂直居中

<div class="ui-flex justify-center center" style="border: green solid 1px;  500px; height: 200px;">
        <div class="cell">
        <img alt="" src="https://www.baidu.com/img/baidu_jgylogo3.gif" style="" />
        </div>
    </div>

<style type="text/css">
        .ui-flex {
            display: -webkit-box !important;
            display: -webkit-flex !important;
            display: -ms-flexbox !important;
            display: flex !important;
            -webkit-flex-wrap: wrap;
            -ms-flex-wrap: wrap;
            flex-wrap: wrap
        }

        .ui-flex, .ui-flex *, .ui-flex :after, .ui-flex :before {
            box-sizing: border-box
        }

        .ui-flex.justify-center {
            -webkit-box-pack: center;
            -webkit-justify-content: center;
            -ms-flex-pack: center;
            justify-content: center
        }
        .ui-flex.center {
            -webkit-box-pack: center;
            -webkit-justify-content: center;
            -ms-flex-pack: center;
            justify-content: center;
            -webkit-box-align: center;
            -webkit-align-items: center;
            -ms-flex-align: center;
            align-items: center
        }
    </style>