src/Color.js
function(amount) {
        var hsl = this.toHSL();
        hsl.l += amount;
        hsl.l = clamp(hsl.l);
        return Color.fromHSL(hsl);
    }
function(amount) {
        var hsl = this.toHSL();
        hsl.l += amount;
        hsl.l = clamp(hsl.l);
        return Color.fromHSL(hsl);
    }
function ( amount ) { var hsl = this . toHSL ( ) ; hsl . l += amount ; hsl . l = clamp ( hsl . l ) ; return Color . fromHSL ( hsl ) ; }
Returns a lighten version of this color

@param amount
value in the range [0..1]
Returns a lighten version of this color