rewrite "^/(\d+)\.html$" /cc// permanent;
This nginx pseudo-static rule, when accessing www.xx.com/404.html, that is, the 404 page in the root directory will jump to /cc/404/
How to modify and resolve the conflict between the content page and the 404 page
error_page 404 /404.html;
It should be possible to uniformly configure the 404 page in this way.