Regina George is riding a bright pink tank. Emblazoned on the tank is the Hexbear logo and the words "Look at this dope ass bear". Above the tank are written the words "get in loser!" and below that the words "We're developing a pretty basic materialist understanding of history based on reading books that weren't written by anti-communist cold warriors and for some reason that's going to piss everyone off and short circuit their brains".
It's a very solid movie about conformity, identity, celebrity, vengeance. Check for cws: it's got some sketchy racist stuff and other problems that are typical of early oughts movies. It's a very important cultural touchstone for a lot of millenials.