app/views/layouts/admin/application.html.erb
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title><%= content_for?(:title) ? yield(:title) : "Event Reserving System" %></title>
<meta name="description" content="<%= content_for?(:description) ? yield(:description) : "Event Reserving System" %>">
<%= stylesheet_link_tag 'admin/base', media: 'all', 'data-turbolinks-track' => true %>
<%= javascript_include_tag 'application', 'data-turbolinks-track' => true %>
<%= csrf_meta_tags %>
</head>
<body>
<%= render 'layouts/admin/top_navigation' %>
<div class="container-fluid">
<div class="row">
<%= render 'layouts/admin/side_navigation' %>
<div class="col-sm-9 col-sm-offset-3 col-md-10 col-md-offset-2 main">
<%= render 'layouts/admin/messages' %>
<main role="main">
<%= yield %>
</main>
</div>
</div>
</div>
</body>
</html>