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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>css叠加性和层叠性</title>
<style>
div{color:green;}
*{font-size:20px;}
</style>
</head>
<body>
<div>
<a href="">css叠加性和层叠性1</a>
<br>
<span class="laoLiu">css叠加性和层叠性2</span>
</div>
</body>
</html>
返回值：