lovecoding
/
VIP26


			
				
					
						
						
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							<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        #box {
            display: flex;
            flex-direction: column;
        }
        #header {
            flex: 1;
            background: #00f;
        }
        /* #header .nav {
            height: 200px;
            background: #ff0;
        } */
        #main {
            flex: 4;
            background: #0f0;
        }
        #footer {
            flex: 1;
            background: #f00;
        }
    </style>
</head>
<body>
    <!-- 主体给宽不给高
        高度我们让内容去撑
    -->
    <div id="box">
        <div id="header">
            <div class="nav">导航</div>
        </div>
        <div id="main">主体</div>
        <div id="footer">页尾</div>
    </div>
</body>
</html>