What are the meanings of these words in The Lovely Bones? "There was a mirror on the shelf, and a razor and shaving cream. I thought that was odd. Wouldn't he do that at home? But I guess I figured that a man who had a perfectly good split-level and then built an underground room only half a mile away had to be kind of loo-loo." (The Lovely Bones） What does a perfectly good split-level mean? And what about the word loo-loo? Thank u.