def sub_nav_item(label, path)
      current_page = current_page?(path)
      content_tag(:dd, class: ("active" if current_page)) do
        link_to label, path
      end
    end
def sub_nav_item(label, path)
      current_page = current_page?(path)
      content_tag(:dd, class: ("active" if current_page)) do
        link_to label, path
      end
    end
Path here must be already resolved to a string using url_for
 e.g. Engine.routes.url_for({controller: .., action: .., only_path: true})