Gog seems to have massive issues rn, I was able to log in but can't change any settings now. I always get an error page. Downdetector also displays 34/43 reports.

You have to go specifically to the giveaway section.

There's a box on the home page for the giveaway, but when I clicked it I got "something went wrong", but as Shimon pointed out, it's free on Steam too, so I nabbed it there.

I can't grab it either. It keeps telling me to log in when I'm already logged in.

its on steam as well if you want to do it that way.