使用在線生成器
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title></title>
</head>
<body>
<header>
<nav></nav>
...
</header>
<div role="main">
...
</div>
<footer>
...
</footer>
</body>
</html>
https://www.cnblogs.com/gbin1/archive/2012/08/10/2631512.html