```ruby
module ApplicationHelper
end
```

Add helper to set class on active navigation items
user
```ruby
module ApplicationHelper

  # Set class on active navigation items
  def nav_link(text, link)
      recognized = Rails.application.routes.recognize_path(link)
      if recognized[:controller] == params[:controller] && recognized[:action] == params[:action]
          content_tag(:li, :class => "active") do
              link_to( text, link)
          end
      else
          content_tag(:li) do
              link_to( text, link)
          end
      end
  end

end
```
assistant