module Playbook::ZIndex

def z_index_props
  selected_props = z_index_options.keys.select { |sk| try(sk) }
  return nil unless selected_props.present?
  responsive = selected_props.present? && try(:z_index).is_a?(::Hash)
  css = ""
  if responsive
    z_index_value = send(:z_index)
    z_index_value.each do |key, value|
      css += "z_index_#{key}_#{value} " if screen_size_values.include?(key.to_s) && z_index_values.include?(value.to_s)
    end
  else
    selected_props.each do |k|
      z_index_value = send(k)
      css += "z_index_#{z_index_value} " if z_index_values.include? z_index_value
    end
  end
  css unless css.blank?
end