Maybe/app/views/accounts/account/_investment.html.erb

<div class="relative p-4 border border-gray-100 bg-offwhite rounded-xl focus-within:bg-white focus-within:shadow focus-within:opacity-100">
  <label for="account_name" class="block text-sm font-medium opacity-50 focus-within:opacity-100">Type</label>
  <%= f.select :subtype, options_for_select(Account::Investment::SUBTYPES, selected: ""), {}, class: "block w-full p-0 mt-1 bg-transparent border-none focus:outline-none focus:ring-0" %>
</div>