huginn/app/views/devise/sessions/new.html.erb

<div class='row'>
  <div class='col-md-6 col-md-offset-3'>
    <div class='well'>

      <h2>Log in</h2>

      <%= form_for(resource, as: resource_name, url: session_path(resource_name), html: { class: 'form-horizontal', role: 'form'}) do |f| %>
        <div class="form-group">
          <%= f.label :login, class: 'col-md-2 col-md-offset-2 control-label' %>
          <div class="col-md-6">
            <%= f.text_field :login, autofocus: true, class: 'form-control' %>
          </div>
        </div>

        <div class="form-group">
          <%= f.label :password, class: 'col-md-2 col-md-offset-2 control-label' %>
          <div class="col-md-6">
            <%= f.password_field :password, class: 'form-control' %>
          </div>
        </div>

        <div class="form-group">
          <div class="col-md-offset-4 col-md-10">
            <% if devise_mapping.rememberable? -%>
              <div class="checkbox">
                <label>
                  <%= f.check_box :remember_me %> <%= f.label :remember_me %>
                </label>
              </div>
            <% end -%>
          </div>
        </div>

        <div class="form-group">
          <div class="col-md-offset-4 col-md-10">
            <%= f.submit "Log in", class: "btn btn-default" %>
          </div>
        </div>
      <% end %>

      <hr>

      <%= render "devise/shared/links" %>
    </div>
  </div>
</div>