Mixed from three paints: Titanium White, Phthalo Blue and Cadmium Yellow.
Drag a bar to change how much of that paint goes in, and watch the colour change at the top.
Parts are a ratio: a drop, a spoonful, whatever suits the amount you need.
Printers' cyan is a blue: Phthalo Blue is the paint that matches it. Lighten with white for the familiar bright cyan.
The library and every recipe here are mixed from just these.