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<!DOCTYPE html>
<html>
<head>
    <style>
        .container{
            border:1px solid black;
            padding:10px;
            
        }
        .content{
            background-color:red;
            width:300px;
            height:200px;
            float:left;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="content"></div>
    </div>
</body>
</html>