full width search input on mobile devices

app/views/submissions_archived/index.html.erb

@@ -1,6 +1,6 @@
 <% filter_params = params.permit(Submissions::Filter::ALLOWED_PARAMS).compact_blank %>
 <div>
-  <%= link_to root_path, class: 'flex items-center' do %>
+  <%= link_to root_path, class: 'flex items-center mb-1 md:mb-0' do %>
     <%= svg_icon('chevron_left', class: 'w-5 h-5') %>
     <span style="margin-left: 3px"><%= t('back_to_active') %></span>
   <% end %>
@@ -10,7 +10,7 @@
     <div>
       <h1 class="text-2xl md:text-3xl font-bold md:block <%= 'hidden' if params[:q].present? %>"><%= t('submissions') %> <span class="badge badge-outline badge-lg align-middle"><%= t('archived') %></span></h1>
     </div>
-    <div>
+    <div class="max-md:focus-within:grow <%= 'max-md:grow' if params[:q].present? %>">
       <% if params[:q].present? || @pagy.pages > 1 || filter_params.present? %>
         <%= render 'shared/search_input', placeholder: "#{t('search')}..." %>
       <% end %>