This is pretty embarrassing. For the past week, the website has been unusable due to an expired certificate. The letsencrypt renewal script was failing, but quietly, so I was not notified about it.
I rarely access that page since I use bitboard directly by accessing http://a.getbitboard.com. The same goes for active users I guess because I can see that people have been using bitboard while this has been a problem.
It’s fixed now. Sorry about that.