<body>
    <div id="wrap">
        <div id="header"></div>
        <div id="nav"></div>
        <div id="aside"></div>
        <div id="section"></div>
        <div id="section2"></div>
        <div id="section3"></div>
        <div id="footer"></div>
    </div>
</body>
<style>
        *{
            margin: 0;
        }
        body{
            background-color: #E1F5FE;
        }
        #wrap{
            width: 1200px;
            margin: 0 auto;

            display: grid;
            grid-template-areas:
            "header header"
            "nav nav"
            "aside section"
            "aside section2"
            "aside section3"
            "footer footer"
            ;
            grid-template-columns: 25% 75%;
            grid-template-rows: 100px 100px 260px 260px 260px 100px;
        }
        #header{
            grid-area: header;
            background-color: #B3E5FC;
        }
        #nav{
            grid-area: nav;
            background-color: #81D4FA;
        }
        #aside{
            grid-area: aside;
            background-color: #4FC3F7;
        }
        #section{
            grid-area: section;
            background-color: #29B6F6;

        }
        #section2{
            grid-area: section2;
            background-color: #03A9F4;

        }
        #section3{
            grid-area: section3;
            background-color: #039BE5;

        }
        #footer{
            grid-area: footer;
            background-color: #0288D1;

        }
        @media(max-width:1280px){
            #wrap{
                width: 96%;
                /* margin: 0 auto; 필요없음*/

                /* display: grid; 필요없음*/
                grid-template-areas:
                "header header header"
                "nav nav nav"
                "aside section section"
                "aside section2 section3"
                "footer footer footer"
                ;
                grid-template-columns: 25% 37.5% 37.5%;
                grid-template-rows: 100px 100px 260px 520px 100px;
            }
        }
        @media(max-width:768px){
            #wrap{
                width: 100%;
                /* margin: 0 auto; 필요없음*/

                /* display: grid; 필요없음*/
                grid-template-areas:
                "header header"
                "nav nav"
                "aside section"
                "aside section2"
                "footer footer"
                ;
                grid-template-columns: 25% 75%;
                grid-template-rows: 100px 100px 390px 390px 100px;
            }
        }
        @media(max-width:480px){
            #wrap{
                /* width: 100%; 이미 768px 였을때 100%여서 필요없음*/
                /* margin: 0 auto; 필요없음*/

                /* display: grid; 필요없음*/
                grid-template-areas:
                "header"
                "nav"
                "aside"
                "section"
                "section2"
                "footer"
                ;
                grid-template-columns: 100%;
                grid-template-rows: 100px 100px 200px 430px 150px 100px;
            }
        }
    </style>

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