Definition
CSS Typed OM Level 1 defines CSSLab
[Exposed=(Window, Worker, PaintWorklet, LayoutWorklet)]
interface CSSLab : CSSColorValue {
constructor(CSSColorPercent l, CSSColorNumber a, CSSColorNumber b, optional CSSColorPercent alpha = 1);
attribute CSSColorPercent l;
attribute CSSColorNumber a;
attribute CSSColorNumber b;
attribute CSSColorPercent alpha;
};