anchor.diff:          <div class="radio">
             <%= f.label :appointment_type, value: 'standard' do %>
               <%= f.radio_button :appointment_type, 'standard',
  -                               class: 't-appointment-type-standard' %>
  +                               class: 't-appointment-type-standard', disabled: f.object.appointment_type != 'standard' %>
               Appointment for customers aged 55+
             <% end %>
           </div>
           <div class="radio">
             <%= f.label :appointment_type, value: '50_54' do %>
               <%= f.radio_button :appointment_type, '50_54',
  -                               class: 't-appointment-type-50-54' %>
  +                               class: 't-appointment-type-50-54', disabled: f.object.appointment_type != '50_54' %>
               Appointment for customers aged 50-54
             <% end %>
           </div>
  
positive.code:     <div class="form-group">
        <%= f.label :date_of_appointment %>
        <%= f.date_field :date_of_appointment,
                         class: %w(form-control input-md-2 t-date-of-appointment) %>
      </div>
  
      <div class="form-group">
        <%= f.label :reference_number %>
        <%= f.text_field :reference_number, class: %w(form-control input-md-2 t-reference-number) %>
      </div>
  
      <div class="form-group">
  
negative.code: 
      <div class="form-group">
        <%= f.label :guider_name %>
        <%= f.text_field :guider_name, class: %w(form-control input-md-3 t-guider-name), readonly: true %>
      </div>
  
      <hr>
  