响应式布局实例操作

*{
    margin: 0px;
    padding: 0px;
}

.heading,
.container,
.footing{
    margin: 10px auto;
}
.heading{
    height: 100px;
    background-color: chocolate;
}
.left,
.right,
.main{
    background-color: cornflowerblue;
}

.footing{
    height: 100px;
    background-color: aquamarine;
}

@media screen and (min- 960px){
    .heading,
    .container,
    .footing{
         960px;
    }

    .left,
    .main,
    .right{
        float: left;
        height: 500px;
    }

    .left,
    .right
    {
         200px;
    }
    .main{
        margin-left: 5px;
        margin-right: 5px;
         550px;
    }
    .container{
        height: 500px;
    }

}

@media screen and (min- 600px) and (max- 960px){
    .heading,
    .container,
    .footing{
         600px;
    }

    .left,
    .main
    {
        float: left;
        height: 400px;
    }
    .right{
        display: none;
    }
    .left{
         160px;
    }
    .main{
         435px;
        margin-left: 5px;
    }
    .container{
        height: 400px;
    }
}

@media screen and (max- 600px){
    .heading,
    .container,
    .footing{
         400px;
    }

    .left,
    .right{
         400px;
        height: 100px;
    }
    .main{
        margin-top: 10px;
         400px;
        height: 200px;
    }
    .right{
        margin-top: 10px;
    }
    .container{
        height: 420px;
    }
}

html

<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <meta name="viewport" content="width = device-width,initial-scale=1">
    <title></title>
    <link href="css/style01.css" type="text/css" rel="stylesheet">
</head>
<body>
    <div class="heading"></div>
    <div class="container">
        <div class="left"></div>
        <div class="main"></div>
        <div class="right"></div>
    </div>
    <div class="footing"></div>
</body>
</html>