Every board is invisible all of a sudden?

A few hours ago, lichess looked perfectly fine for me, but logging on just now I saw that I can only see the pieces, but no board. It's just a black background. Is anyone else seeing this?

To elaborate more on it, it's happening for every board, even the captcha's and the analysis board

Same thing here. Changing the board theme fixes the issue (click on your username and select "Board theme").