sessions/new.html.erb for devise and bootstrap 3.x

new.html.erb

<div class="row">
	<div class="col-sm-offset-2 col-sm-4">
		<h1>Sign in</h1>
	</div>
</div>

<hr>

<div class="row">
	<%= form_for(resource, :as => resource_name, :url => session_path(resource_name), html: { class: 'form-horizontal' }) do |f| %>
		<div class="form-group">
		  <label class="col-sm-2 control-label"><%= f.label :email %></label>
		  <div class="col-sm-4">
		    <%= f.email_field :email, class: 'form-control', :autofocus => true %>
		  </div>
		</div>
		<div class="form-group">
		  <label class="col-sm-2 control-label"><%= f.label :password %></label>
		  <div class="col-sm-4">
		    <%= f.password_field :password, class: 'form-control' %>
		  </div>
		</div>

		<% if devise_mapping.rememberable? -%>
			<div class="form-group">
			  <div class="col-sm-offset-2 col-sm-4">
			    <div class="checkbox">
			      <label>
			        <%= f.check_box :remember_me %> <%= f.label :remember_me %>
			      </label>
			    </div>
			  </div>
			</div>
		<% end -%>

		<div class="form-group">
		  <div class="col-sm-offset-2 col-sm-4">
		  	<%= f.submit "Sign in", class: 'btn btn-primary' %>
		  </div>
		</div>
	<% end %>
</div>

<hr>

<div class="row">
	<div class="col-sm-offset-2 col-sm-3">
		<%= render "devise/shared/links" %>
	</div>
</div>