The color green symbolizes life and success. The light at the end of the dock is something Gatsby looks towards and symbolically this is him looking to find success. Blue is a symbol of fantasy and romanticized ideals (things that cannot be because they are untrue). Daisy is also symbolic of a romantic dream for Gatsby. He imagines her better, sweeter, etc. than she really is. She is unattainable because Gatsby's Daisy, the one he invents in his mind and heart, does not exist.
