2CSS层叠规则(即引入CSS的三种不同方式的优先级)
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title></title>
<!--外部样式表-->
<link rel="stylesheet" href="../css/helloWorld.css" />
<!--内部样式表-->
<style type="text/css">
body{
background-color:yellow;
}
/* 修饰同一选择符的样式时，后修饰的覆盖前修饰的样式
* body{
background-color:deeppink;
}*/
</style>
<link rel="stylesheet" href="../css/helloWorld2.css" />
<!--内部样式表和外部样式表是平级关系,在html中，谁后定义样式，则会覆盖前面的样式 平级关系 -->
</head>
<body>
<!-- <body style="background-color: green;"> 内部样式表 优先级最高 -->
<!-- 浏览器缺省样式：就是浏览器默认的样式，不同浏览器默认样式不同 优先级最低 -->
<body>
</body>
</html>
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