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console

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>盒子模型</title>
    <link rel="stylesheet" type="text/css" href="css/NaVi.css">
</head>

<body>
    <div id="box1">
        <div id="text">学习CSS很重要</div>
    </div>
    <div id="box2">盒子模型需要认真理解</div>
</body>

</html>

body {
    margin: 0;
    padding: 0;
}

#box1 {
    background-color: red;
    margin: 20px;
    border: 10px solid black;
    padding: 40px;
    width: 200px;
}

#text {
    background-color: yellow;
    height: 100px;
}

#box2 {
    background-color: blue;
    margin: 5px;
    height: 100px;
    padding-left: 30px;
}