https://www.iana.org/assignments/language-subtag-registry/language-subtag-registry
www.html.cn/book/css/properties/media-queries/orientation.htm#a3 这里的写法
<html lang="zh-cmn-Hans">
已经不再推荐了。。
PHP
https://www.iana.org/assignments/language-subtag-registry/language-subtag-registry
www.html.cn/book/css/properties/media-queries/orientation.htm#a3 这里的写法
<html lang="zh-cmn-Hans">
已经不再推荐了。。