i think blue matches or probably yellow if you just try black it will work with any colour except black.
It's a little bland of a color combination but it would definitely work if you worked it!
Gunmetal-gray is considered a dark color. It is a shade of gray that has a slightly metallic finish, giving it a darker and cooler tone.
The opposite to gray is gray dark gray is light gray ;)
Charcoal is a dark gray color.
Dark gray.
gray converse
Charcoal is typically black in color, with variations in shades from dark gray to black depending on the type and quality of the charcoal.
Gray is said to be dark and dismal as in gloomy gray skies
gray
dark gray, brown, greenish
Paul's wolf form is described as dark gray with silver-gray fur.
A nasty color