app/views/layouts/application.html.erb
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=no">
<title><%= t('app_name') %></title>
<!-- CDN installation -->
<%= javascript_include_tag "//code.jquery.com/jquery-2.1.4.min.js" %>
<%= javascript_include_tag "//maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js" %>
<%= stylesheet_link_tag "//maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css" %>
<!-- Rails Default settings -->
<%= stylesheet_link_tag 'application', media: 'all', 'data-turbolinks-track' => true %>
<%= javascript_include_tag 'application', 'data-turbolinks-track' => true %>
<%= csrf_meta_tags %>
</head>
<body id="<%= "#{controller.controller_name}" %>">
<%= render 'shared/header' %>
<%= render 'shared/nav' %>
<% if notice %>
<p class="alert alert-success"><%= notice %></p>
<% end %>
<% if alert %>
<p class="alert alert-danger"><%= alert %></p>
<% end %>
<article>
<div class="container">
<%= yield %>
</div>
</article>
<%= render 'shared/footer' %>
</body>
</html>