I'm trying to make an application that can login to a browser game (Click here for the English version of it). I know how to login to a simple PHP login that doesn't use cookies, but I'm not familiar with this - tbh, I have no clue how to do this.

I googled a bit, but couldn't find any useful hits.

If anyone knows how I could login on this page - or login with cookies in general (I think I can figure out the rest myself), it'll be greatly appreciated.