<%= simple_form_for(@contact_form,
url: { action: 'contact' },
html: { method: :post, class: 'form-horizontal' }
) do |f| %>
<%= error_messages_for(@contact_form) %>
<%= f.text_field :nickname %>
<%= f.input :name, label: 'Your name' %>
<%= f.input :email, label: 'Your email' %>
<%= f.input :file, as: :file, hint: 'can be attached optionally' %>
<%= f.input :message, as: :text, input_html: { rows: 10 } %>
<%= f.submit 'Send', :class => 'btn btn-primary' %>
<% end %>