页面布局
HTML5 提供的新语义元素定义了网页的不同部分：
| 元素名 | 描述 |
|---|---|
| header | 标记头部区域的内容（用于页面或页面中的一块区域） |
| footer | 标记脚部区域的内容（用于整个页面或页面的一块区域） |
| section | Web页面中的一块独立区域 |
| article | 独立的文章内容 |
| aside | 相关内容或应用（常用于侧边栏） |
| nav | 导航类辅助内容 |
| details | 定义额外的细节 |
| summary | 定义details元素的标题 |
示例：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
header {
background-color: black;
color: white;
text-align: center;
padding: 5px;
}
nav {
line-height: 30px;
background-color: #eeeeee;
height: 300px;
width: 100px;
float: left;
padding: 5px;
}
section {
width: 350px;
float: left;
padding: 10px;
}
footer {
background-color: black;
color: white;
clear: both;
text-align: center;
padding: 5px;
}
</style>
</head>
<body>
<header>
<h1>City Gallery</h1>
</header>
<nav>
London<br>
Paris<br>
Tokyo<br>
</nav>
<section>
<h1>London</h1>
<p>
London is the capital city of England. It is the most populous city in the United Kingdom,
with a metropolitan area of over 13 million inhabitants.
</p>
<p>
Standing on the River Thames, London has been a major settlement for two millennia,
its history going back to its founding by the Romans, who named it Londinium.
</p>
</section>
<footer>
Copyright W3Schools.com
</footer>
</body>
</html>
