kind-view-controller()
  $view = $this.strings[0] or '&-view'
  $controller = $this.strings[1] or '&-controller'

  {$controller}
    kind-hidden(visually)
    // Could add `.is-disabled &\n kind: hidden`

  if checked in arguments
    input:checked + {$view}
      skin: button_checked

  if focus in arguments
    :focus + {$view}
      skin: button_focus