= form_for @pv_query, :validate => true, remote: true, class: 'form-horizontal' do |f|
  = render 'shared/error_messages', object: f.object
  fieldset.row
    .col-xs-12.col-sm-4
      .form-group
        = f.label :postcode_id, 'Postcode', min: '221', max: '9999', class: 'col-xs-3 col-sm-5 control-label'
        = f.number_field :postcode_id, class: 'form-control'
  = f.fields_for :panels do |builder|
    = render 'panel_fields', f: builder
  = link_to 'add panel', '', class: 'btn btn-default add_fields', remote: true
  = f.submit 'view output', class: "btn btn-default btn-primary"

= form_for @pv_query, :validate => true, remote: true, html: {class: 'form-horizontal'} do |f|
  = render 'shared/error_messages', object: f.object
  fieldset.row
    .col-xs-12.col-sm-4
      .form-group
        = f.label :postcode_id, 'Postcode', min: '221', max: '9999', class: 'col-xs-3 col-sm-5 control-label'
        = f.number_field :postcode_id, class: 'form-control'
  = f.fields_for :panels do |builder|
    = render 'panel_fields', f: builder
  = link_to 'add panel', '', class: 'btn btn-default add_fields', remote: true
  = f.submit 'view output', class: "btn btn-default btn-primary"

Update form_for to rails 4.
Update form_for to rails 4.

studiospring/solario,studiospring/solario,studiospring/solario