favicon
在未指定 favicon 时，大多数浏览器会请求 Web Server 根目录下的 favicon.ico 。为了保证 favicon 可访问，避免404，必须遵循以下两种方法之一：
- 在 Web Server 根目录放置 favicon.ico 文件；
- 使用 link 指定 favicon；
<link rel="shortcut icon" href="path/to/favicon.ico">
移动端页头推荐配置
<meta charset="UTF-8">
<title>title</title>
<meta name="keywords" content="" />
<meta name="description" content="" />
<meta name="viewport" content="width=640,user-scalable=no" />
<!--<meta name="viewport" content="initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0,user-scalable=no,minimal-ui">-->
<meta http-equiv="cleartype" content="on">
<meta name="apple-mobile-web-app-title" content="...">
<meta name="apple-mobile-web-app-capable" content="yes">
<meta name="format-detection" content="telephone=no">
<meta http-equiv="x-rim-auto-match" content="none">
<meta name="apple-touch-fullscreen" content="yes">
<meta name="apple-mobile-web-app-status-bar-style" content="black">
<!-- uc强制竖屏 -->
<meta name="screen-orientation" content="portrait">
<!-- QQ强制竖屏 -->
<meta name="x5-orientation" content="portrait">
<!-- UC强制全屏 -->
<meta name="full-screen" content="yes">
<!-- QQ强制全屏 -->
<meta name="x5-fullscreen" content="true">