代码
<!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>简单的小后台</title>
</head>
<body>
<!-- 头部 -->
<header>
<h1>网站后台管理系统 <small>(V.1.0)</small></h1>
<em>admin</em>
<button onclick="location.href='logout.php'">退出</button>
</header>
<!-- 导航 -->
<nav>
<a href="../1004/demo.html" target="content">元素属性</a>
<a href="../1004/demo.html" target="content">元素属性</a>
<a href="../1004/demo.html" target="content">元素属性</a>
<a href="../1004/demo.html" target="content">元素属性</a>
<a href="../1004/demo.html" target="content">元素属性</a>
<a href="../1004/demo.html" target="content">元素属性</a>
</nav>
<!-- 内容 -->
<iframe src="" frameborder="0" name="content"></iframe>
</body>
</html>