I sometimes use these functions when rapidly prototyping. I can store one or more base colors, and then calculate other shades of colors relative to the base. T

I sometimes use these functions when rapidly prototyping. I can store one or more base colors, and then calculate other shades of colors relative to the base. This makes changing the site's color scheme a matter of changing just the base color(s). Of course, once I've settled on final colors, I may go in and tweak all of the shades with exact values.