We are working on making the website independent of the PoE realm, but the website was originally built with the assumption that the game is up and they are deployed together.
We hope to have this done by 3.6.0 deploy, but I can't promise it will be then.
After we are done, when the game is down you wont be able to do things like view your character or link items in the forums, but you will still be able to use the website generally.