public function toRGB()
    {
        $h = $this->hue;
        $s = $this->saturation / 100;
        $l = $this->lightness / 100;
        $r;
        $g;
        $b;
        $c = (1 - abs(2 * $l - 1)) * $s;
        $x = $c * (1 - abs(fmod(($h / 60), 2) - 1));
        $m = $l - ($c / 2);
        if ($h < 60) {
            list($r, $g, $b) = [$c, $x, 0];
        } elseif ($h < 120) {
            list($r, $g, $b) = [$x, $c, 0];
        } elseif ($h < 180) {
            list($r, $g, $b) = [0, $c, $x];
        } elseif ($h < 240) {
            list($r, $g, $b) = [0, $x, $c];
        } elseif ($h < 300) {
            list($r, $g, $b) = [$x, 0, $c];
        } else {
            list($r, $g, $b) = [$c, 0, $x];
        }
        $r = ($r + $m) * 255;
        $g = ($g + $m) * 255;
        $b = ($b + $m) * 255;

        return [
            round($r),
            round($g),
            round($b),
        ];
    }