I've realized that I'm not sure I understand the British use of the word, "Cheers."
It seems to be used as a sort of acknowledgment of something someone else said. To me it seems as though it should be happy, but I don't think it's always used that way.
Person 1: That book you were waiting for is coming out next week.
Person 2: Cheers.
Alright, that might be a person being happy about the news, but I'm sure I've seen it used in other ways that didn't strike me as inherently happy. And those sorts of uses were kind of jarring to me and made me think, "Wait. What did he mean by that?"
My daughter thinks it may mean, "Thanks."
I'm just not sure.