Math/Art Nerd Slang: Something that is attractive or good, usually because its dimensions or aspects closely match that of The Golden Ratio, approximately 1:1.618... a ratio that has been described as the mathematical Ratio for beauty. The number 1.618.... is a mathematical constant known as Phi, therefore things that are beautiful ("Fine") are usually also "Phine".
Guy: "Did you see that girl?"
Dude: "Yeah, She was Phine! Her ratios were golden!"