移动Web开发必备基础之媒体查询

媒体类型：

all （默认值）

screen

print 打印设备

speech 屏幕阅读器

由于all是默认值可不写，因此以下两种写法效果相同

@media all and (min-900px){

}


@media (min-900px){

}

媒体查询中的逻辑

与或非

@media (min-900px) and (max-1024px){

}

媒体特征表达式

width / max-width / min-witdh

-webkit-device-pixel-ratio / -webkit-max-device-pixel-ratio / -webkit-min-device-pixel-ratio

orientation: landscape / portrait 横屏 / 竖屏

媒体查询-策略

移动端断点（参考bootstrap）

xs <576px 1

sm 576~768px 2

md 768~992px 4

lg 992~1200px 6

xl >1200px 12

后面的条件满足时，会覆盖前面的条件

PC first

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <link rel="stylesheet" href="font/iconfont.css">
    <style>
        *{margin:0;padding:0;box-sizing:border-box;}
        img{width:100%;}
        .row{width:100%;display: flex;flex-wrap:wrap;}

        /*pc first*/
        .col{width:8.33%;}
        @media (max-1200px){
            .col{width:16.67%;}
        }
        @media (max-992px){
            .col{width:25%;}
        }
        @media (max-768px){
            .col{width:50%;}
        }
        @media (max-576px){
            .col{width:100%;}
        }

    </style>
</head>
<body>
    <div class="row">
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
    </div>
</body>
</html>

mobile first

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width,initial-scale=1,user-scalable=no,maximum-scale=1,minimum-scale=1">
    <title>Document</title>
    <link rel="stylesheet" href="font/iconfont.css">
    <style>
        *{margin:0;padding:0;box-sizing:border-box;}
        img{width:100%;}
        .row{width:100%;display: flex;flex-wrap:wrap;}

        /*mobile first*/
        .col{width:100%;}
        @media (min-576px){
            .col{width:50%;}
        }
        @media (min-768px){
            .col{width:25%;}
        }
        @media (min-992px){
            .col{width:16.67%;}
        }
        @media (min-1200px){
            .col{width:8.33%;}
        }

    </style>
</head>
<body>
    <div class="row">
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
        <div class="col">
            <img src="img/cyy.jpg">
        </div>
    </div>
</body>
</html>

效果同上

一般建议mobile first （移动优先）

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原文地址：https://www.cnblogs.com/chenyingying0/p/12493173.html