mastodon/app/views/layouts/admin.html.haml

- content_for :content do
  .admin-wrapper
    .sidebar-wrapper
      .sidebar
        = link_to root_path do
          = image_tag asset_pack_path('logo.svg'), class: 'logo', alt: 'Mastodon'

        = render_navigation
    .content-wrapper
      .content
        %h2= yield :page_title

        = render 'application/flashes'

        = yield

= render template: 'layouts/application', locals: { body_classes: 'admin' }