<div class="field-unit__label">
  <%= f.label field.attribute %>
</div>
<div class="field-unit__field">
  <%= image_tag(field.url, style: "background-color:#d9d9d9;max-width:100px", alt: field.attribute.to_s.humanize) if field.url %>
  <br />
  <%= f.file_field field.attribute %>
</div>
