{{vinli-button
  action=(action parent.actions.toggleExpandAside)
  icon='side-bar-arrow'
  icon-position='after'
  size='small'
  theme='light'
  class=(concat 'expanding-aside__toggle-btn' (if isCollapsed ' expanding-aside__toggle-btn--collapsed'))}}

<div class="expanding-aside__content">
  {{yield}}
</div>