你的值没问题，但是 meta http-equiv 非常不可靠.您应该使用真正的 HTTP 标头(具体如何操作取决于您的服务器，例如 对于 Apache).

The values you have there are OK, but meta http-equiv is highly unreliable. You should be using real HTTP headers (the specifics of how you do this will depend on your server, e.g. for Apache).