<body>
    <div id="wrap">
        <div id="header"></div>
        <div id="nav"></div>
        <div id="aside"></div>
        <div id="section"></div>
        <div id="article"></div>
        <div id="footer"></div>
    </div>
</body>
<style>
        *{
            margin: 0;
        }
        #wrap {
            width: 1200px;
            margin: 0 auto;
        }
        #body{
            background-color: #E8F5E9;
        }

        #header{
            width: 100%;
            height: 100px;
            background-color: #C8E6C9;
        }
        #nav{
            width: 100%;
            height: 100px;
            background-color: #A5D6A7;
        }
        #aside{
            width: 20%;
            height: 780px;
            background-color: #81C784;
            float: left;
        }
        #section{
            width: 60%;
            height: 780px;
            background-color: #66BB6A;
            float: left;
        }
        #article{
            width: 20%;
            height: 780px;
            background-color: #4CAF50;
            float: left;
        }
        #footer{
            width: 100%;
            height: 100px;
            background-color: #43A047;
            clear: both;
        }
        @media(max-width: 1280px){
            #wrap {
                width: 96%;
                margin: 0 auto;
            }
        }
        @media(max-width: 768px){
            #wrap {
                width: 100%;
            }
            #aside{
                width: 20%;
                height: 780px;
                float: left;
            }
            #section{
                width: 80%;
                height: 780px;
                float: left;
            }
            #article{
                width: 100%;
                height: 150px;
            }
        }
        @media(max-width: 480px){
            #wrap {
                width: 100%;
            }
            #aside{
                width: 100%;
                height: 200px;
            }
            #section{
                width: 100%;
                height: 430px;
            }
            #article{
                width: 100%;
                height: 150px;
            }
        }
    </style>

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