app/views/users/_email_alert.html.erb
<div class="alert alert-dismissible alert-info">
<button type="button" class="close" data-dismiss="alert">×</button>
<h4>Stay up to date!</h4>
<p>Enter your email to get automatic notifications of friend requests, loan requests, and other activity.</p>
<div class="panel-body">
<%= form_for current_user do |f| %>
<%= f.label :email_address %>: <%= f.text_field :email, style: "color: black;" %> <%= f.submit "Submit", class: "btn btn-default btn-sm" %>
<% end %>
</div>
</div>