static function base($url = '', $cacheBuster = false) {
        $cacheb = $cacheBuster ? ('?' . (Config::get('app.version', '1.0.0'))) : ''; 
        $servern = $_SERVER['SERVER_NAME']; 
        $serverp = $_SERVER['SERVER_PORT'];
        $server = $serverp == '8080' || $serverp == '80' || $serverp == '443' ? $servern : "$servern:$serverp";

        return (((isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on') ||
                (!empty($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] == 'https' || !empty($_SERVER['HTTP_X_FORWARDED_SSL']) && $_SERVER['HTTP_X_FORWARDED_SSL'] == 'on'))
                    ? 'https://' : 'http://') . str_replace('//', '/', ($server . '/' . $url)) . $cacheb;
    }