Amy Winehouse

These answers about the speed of light only cause more questions.?

Scientist say nothing can travel at the speed of light but light does. The simple explanation that travelling at the speed of light means it would increase to infinite mass must mean that light has no mass otherwise it would already be infinite in size. Does green laser light travel at the same speed as red laser light? Since these are related only by frequency does the doppler effect come into play?
Pardon my ignorance but I’m still confused. The science channel says that a light on a spaceship moving at say 0.5 x speed of light will still only move towards me at the speed of light and not 1.5 times the speed of light. So how can a red laser beam conform to the doppler theory. It seems that it would be impossible to accelerate a red laser on a spaceship towards me so that as it approached me it looked say green.