.sidebar a.sidebar-link[role=button]{position:relative}.sidebar a.sidebar-link[role=button]:before{content:" ";border:.1rem solid;border-width:0 .1rem .1rem 0;padding:2px;transition:all .2s ease-out;display:inline-block;position:absolute;top:1rem;right:1.7rem;transform:rotate(45deg)}.sidebar a.sidebar-link[role=button][aria-expanded=true]:before{top:1.2rem;transform:rotate(-135deg)}