<%# Usage: render 'content/form/relation_input', f: f, attribute: attribute, relation: through_class %>
<%= f.label attribute, I18n.translate( "attributes.#{f.object.class.name.downcase}.#{attribute}", scope: :activerecord, default: label.humanize.capitalize ) %>
<%= f.fields_for relation do |builder| %> <%= render 'content/form/groupship_fields', f: builder, attribute: attribute.singularize, parent: f.object %> <% end %>
<% model_class = f.object.send(attribute).build.class %> <% color = model_class.color %> <%= link_to_add_association "link #{model_class.name.downcase}", f, relation, class: "btn #{color}", partial: 'content/form/groupship_fields', render_options: { locals: { attribute: attribute.singularize, parent: f.object }} %>