public function postClass($classes = [])
    {
        $classes = !is_array($classes) ? explode(' ', $classes) : $classes;
        $classes[] = 'content-node';

        $classes = apply_filters('novusopress_view_post_classes', get_post_class($classes));
        $output = sprintf('class="%s"', implode(' ', $classes));

        return apply_filters('novusopress_view_post_class_output', $output);
    }