<GlobalHeader
  @class="page-header"
  @onHamburgerClick={{action (mut this.isGutterOpen) true}}>
  <AppBreadcrumbs />
</GlobalHeader>
<GutterMenu
  @class="page-body"
  @isOpen={{this.isGutterOpen}}
  @onHamburgerClick={{action (mut this.isGutterOpen) false}}>
  {{yield}}
</GutterMenu>
