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<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=no">
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<style>
@media screen and (min-width: 300px) and (max-width: 500px) {
body {
background-color:green;
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}
@media screen and (min-width: 501px) and (max-width:800px){
body {
background-color:lightblue;
}
}
@media screen and (min-width:801px){
body {
background-color:orange;
}
}
</style>
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<body>
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<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=no">
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<script src="https://oss.maxcdn.com/libs/html5shiv/3.7.0/html5shiv.js"></script>
<script src="https://oss.maxcdn.com/libs/respond.js/1.3.0/respond.min.js"></script>
<![endif]-->
<meta http-equiv="X-UA-Compatible" content="IE=Edge，chrome=1">
<style>
@media screen and (min-width: 300px) and (max-width: 500px) {
body {
background-color:green;
}
}
@media screen and (min-width: 501px) and (max-width:800px){
body {
background-color:lightblue;
}
}
@media screen and (min-width:801px){
body {
background-color:orange;
}
}
</style>
<title>无标题文档</title>
</head>
<body>
</body>
</html>