app/views/devise/confirmations/new.html.erb
<%= bootstrap_devise_error_messages! %>
<div class="panel panel-default devise-bs">
<div class="panel-heading">
<h4><%= t('.resend_confirmation_instructions', :default => 'Resend confirmation instructions') %></h4>
</div>
<div class="panel-body">
<%= form_for(resource, :as => resource_name, :url => confirmation_path(resource_name), :html => { :method => :post, role: "form" }) do |f| %>
<div class="form-group">
<%= f.label :email %>
<%= f.email_field :email, autofocus: true, class: "form-control" %>
</div>
<%= f.submit t('.resend_confirmation_instructions', :default => 'Resend confirmation instructions'), class: "btn btn-primary" %>
<% end %>
</div>
</div>
<%= render "devise/shared/links" %>