1.派生选择器
<html>
<head>
<link href="a1.css" type="text/css" rel="stylesheet">
</head>
<body>
<h1>ayaya</h1>
</body>
</html>
h1{
color:blue;
}
2.id选择器
<html>
<head>
<link href="a1.css" type="text/css" rel="stylesheet">
</head>
<body>
<p class="pclasss">ayaya</p>
</body>
</html>
#h1id{
color:blue;
}
3.类选择器
<html>
<head>
<link href="a1.css" type="text/css" rel="stylesheet">
</head>
<body>
<h1 id="h1id">This is my page</h1>
This is my JSP page
</body>
</html>
.pclasss
{
color:red;
}