Leafo\ScssPhp\Compiler::libUniqueId PHP Method

    protected function libUniqueId()
    {
        static $id;
        if (!isset($id)) {
            $id = mt_rand(0, pow(36, 8));
        }
        $id += mt_rand(0, 10) + 1;
        return [Type::T_STRING, '', ['u' . str_pad(base_convert($id, 10, 36), 8, '0', STR_PAD_LEFT)]];
    }