Your Offline site mode is the inherentable insecure and it's not supportable.
Can you elaborate?
Deploy NodeBB in a subfolder of a site
nodebb doc link website offline
Text Games in site
Login when maintenance mode is active?
NodeBB and other web sites on the server
How to get to the site files?
How to put the NodeBB to a site like one whole site
New site on NodeBB hosting