constructor(h, s, l, a = 1) {
		this.h = h;
		this.s = s;
		this.l = l;
		this.a = a;
	}
HSL color constructor
@param {number} h Hue value between 0 and 1
@param {number} s Saturation value between 0 and 1
@param {number} l Lightness value between 0 and 1
@param {number} a Alpha value between 0 and 1