The WCAG contrast ratio between two colors, from 1 to 21 (commonly written 1:1 to 21:1).
- The first color, often the background color.
- The second color, often the foreground color.
- A number representing the contrast ratio between two colors.
@debug color.contrast(white, red);
@debug color.contrast(#fff, #000);
@debug color.contrast(blue, #00f);