app/views/auctions/_bid_form.html.erb
<%= simple_form_for Bid.new,
url: auction_bids_path(status.auction_id), class: "usa-form-large" do |f| %>
<fieldset>
<div class="usa-input-grid usa-input-grid-small">
<%= f.input :amount, required: false %>
</div>
<div class="usa-input-grid usa-input-grid-small">
<%= f.submit class: 'usa-button usa-button-outline action-button' %>
</div>
</fieldset>
<% end %>