public static function config(array $config = []) {
		if (!$config) {
			return ['classes' => static::$_classes];
		}

		foreach ($config as $key => $val) {
			$key = "_{$key}";

			if (isset(static::${$key})) {
				static::${$key} = $val + static::${$key};
			}
		}
	}