app/views/layouts/admin.html.haml

!!! 5
%html{ lang: "en"}
  = render 'layouts/head'
  %body{ :'data-page' => body_data_page }
    = render 'layouts/nav'
    = render 'layouts/info'
    - if content_for?(:title)
      .container.container-title
        = yield(:title)
      %hr

    .container
      .row
        .col-md-2.append-bottom-20
          = render 'layouts/nav_admin'
        .col-md-10
          = yield