Mothereffing HSL one sec, bro. HSL(a) is the jam. It's a piece of cake to do mentally, too. Hue is like this: ROY G BIV is 0 to 300, and then back to red again at 360. Saturation % is from grey to intense color; lightness % and alpha 0-1 are easy 'nuff. read more on hsl awesomeness.