u/Aggressive-Wish4657

Decided I wanted to do expand on a custom as if it were to be used in the build fighters universe so I added the ahab resonance system (a modified RG system) which illuminates the arms in red and can coat the exia blade in particles to cut thru beams. Can also fire railguns thru the plabsky gate to increase speed and power. Shields act as funnels and absorb beams

Im wanting to make the psychoframe on the shield go from a metallic blue to a red starting from the tip down to the center. I don't own an airbrush at the moment nor can I really afford one. Is there anyway to do this with just the gundam markers