<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
.main{
width: px;
height: px;
border: px solid red;
margin: auto;
padding:px;
box-sizing: border-box;
}
</style>
</head>
<body>
<div class="main">啊水水水水水水水水水水水水水水水水是</div>
</body>
</html>
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