Deep Purple : Special Effects SFX Hair Color Hair Dye

How does this work on naturally white hair? I started going grey EARLY!! And now I'm mostly blondish-white.

If I use Blue Mayhem over Colour Effects Fuschia (faded to a very light, brassy pink), would it still come out blue?

I have naturally dark blonde hair, with light blonde highlights. I'd like to do ONLY a section pink - does this bleed much after initial rinsing?

I have thick shoulder length hair. Would it cover it all?