lovecoding
/
vipAllDay


			
				
					
						
						
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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>
        * {
            box-sizing: border-box;
        }
        /* 
            盒模型：
                标准盒模型：width = 内容宽度 + border + padding :box-sizing: content-box;
                怪异盒模型（IE盒模型）：width = 内容宽度（border + padding +内容宽度）：box-sizing: border-box;

        */
        #box1 {
            width: 300px;
            height: 300px;
            background: #00f;
            border: 3px solid #000;
            padding: 20px;
            margin: 20px;
        }
    </style>
</head>
<body>
    <div id="box1"></div>
</body>
</html>