app/views/case_studies/_case_study_card.html.erb
<div class="card">
<div class="card-header bg-positive"><%= case_study.title %></div>
<div class="card-body">
<div class="card-text">
<%= case_study.description %>
</div>
</div>
<div class="card-footer case-studies-download-links" data-event-value="<%= case_study.id %>">
<% download_locale = (I18n.locale.to_sym == :cy && case_study.t_attached(:file, :cy).present?) ? :cy : :en %>
<%= link_to url_for( controller: :case_studies, action: :download, serve: :download, id: case_study.id, :locale => download_locale ), class: 'btn' do %>
<%= t('case_studies.download') %>
<i class="fas fa-file-download"></i>
<% end %>
</div>
</div>