:root{
  --font-sans: 'Instrument Sans', ui-sans-serif, system-ui, sans-serif, 'Apple Color Emoji','Segoe UI Emoji','Segoe UI Symbol','Noto Color Emoji';
}
.sidebar .nav-link{ border-radius:.75rem; }
.sidebar .nav-link.active{ color:#fff!important; background-color:var(--bs-primary); }

/* caret rotate */
.sidebar .nav-link .bi-caret-down-fill{ transition:transform .2s; }
.sidebar .nav-link[aria-expanded="true"] .bi-caret-down-fill{ transform:rotate(180deg); }

/* Submenu */
.sidebar .collapse .nav{ margin:.25rem 0 .5rem; padding:0; }
.sidebar .collapse .nav-link{ display:block; padding:.375rem .75rem; line-height:1.25; }
/* Smooth, tapi tetap Bootstrap-native */
.sidebar .collapsing{ transition: height .25s cubic-bezier(.4,0,.2,1); } /* default .35s ease */