public static function style($file, array $attributes = NULL, $protocol = NULL, $index = FALSE)
    {
        if (strpos($file, '://') === FALSE)
        {
            // Add the base URL
            $file = Ioc::url($file);
        }
    
        // Set the stylesheet link
        $attributes['href'] = $file;
    
        // Set the stylesheet rel
        $attributes['rel'] = 'stylesheet';
    
        // Set the stylesheet type
        $attributes['type'] = 'text/css';
        
        return '<link' . self::attributes($attributes) .' />';
    }