<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>网站后台管理系统</title>
<style>
/ 语法
选择器 {属性：值;}
/
h2 {
color: red;
}
h2[title=”PHP.cn学员”] {
color: #2f00ff;
border: #2f00ff solid 1px;
}
/ 群组选择器 /
h1,
em,
section,
a {
border: #2f00ff solid 1px;
}
a {
color: black;
}
h1 {
color: red;
}
</style>
</head>
<body>
<!-- ?1 后台的顶部 -->
<header>
<h1>网站后台管理</h1>
<section>
<em>admin</em><button onclick="location.hred='logout.php'">退出</button>
</section>
</header>
<!-- ?2后台左侧菜单 -->
<nav>
<a href="1018.html" target="content">第1课</a>
<a href="1019-01.html" target="content">第2课</a>
<a href="1019-02.html" target="content">第3课</a>
<a href="1017.html" target="content">第4课</a>
</nav>
<!-- ?3后台右侧和内容 -->
<iframe
srcdoc="请操作需要的功能"
src=""
frameborder="0"
name="content"
width="600"
height="500"
></iframe>
<!-- ?后台底部 -->
<footer>
<section><em>底部信息</em></section>
</footer>
</body>
</html>
