\definecolor

Syntax

\definecolor[...][...,...=...,...]
[...]	name
r	text red channel (RGB)
g	text green channel (RGB)
b	text blue channel (RGB)
c	text cyan channel (CMYK)
m	text magenta channel (CMYK)
y	text yellow channel (CMYK)
k	text black channel (CMYK)
s	text Gray value (Grayscale)
s	text Saturation (HSB)
v	text Brightness/Value (HSB)
t	text transparency factor
a	text alternative (transparency method? use 1)
p	text spotcolor percentage
e	text spotcolor name
x	text Hexadecimal RGB value (like in HTML)

\definecolor associates a name with a color, for later use with the \color command.

To use hexadecimal colors in mkii you need to load the proper module first:

\setupcolor[hex]

Then the colors can be specified with

\definecolor[hex-red][h=FF0000]