What color should I paint my nails?

What color should I paint my fingernails & toenails for a prom that I'm going to as a guest? My dress is short, strapless and black, my clutch is a beige color with diamonds, I have silver sparkly high heels & my earrings are black diamonds that hang down. I would prefer painting my fingernails a different color then my toes. What are your suggestions for both?? My makeup is going to he very simple.