#sidebar {
  grid-column: 1;
  grid-row: 2;
  background: var(--panel);
  border-right: 1px solid var(--border);
  overflow: hidden;
  padding: 0.5rem 0;
  display: flex;
  flex-direction: column;
}

nav { display: flex; flex-direction: column; gap: 2px; padding: 0 0.4rem; flex: 1; }

.nav-item {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  padding: 0.55rem 0.6rem;
  border-radius: 6px;
  text-decoration: none;
  color: var(--muted);
  font-size: 0.88rem;
  white-space: nowrap;
  transition: color 0.15s, background 0.15s;
  overflow: hidden;
}
.nav-item:hover { color: var(--text); background: rgba(255,255,255,0.05); }
.nav-item.active { color: var(--accent); background: rgba(79,140,255,0.1); }
.nav-item[hidden] { display: none; }

.nav-icon {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.nav-icon svg { width: 18px; height: 18px; }

.nav-label { transition: opacity 0.15s; }

body.sidebar-collapsed .nav-label { opacity: 0; pointer-events: none; }

/* ── Sidebar collapse button ─────────────────────────────────────────── */

#sidebar-collapse-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  padding: 0.6rem 0;
  margin-top: auto;
  background: none;
  border: none;
  border-top: 1px solid var(--border);
  color: var(--muted);
  cursor: pointer;
  transition: color 0.15s, background 0.15s;
}
#sidebar-collapse-btn:hover { color: var(--text); background: rgba(255,255,255,0.04); border-color: var(--border); }
#sidebar-collapse-btn svg { width: 16px; height: 16px; transition: transform 0.22s ease; }
body.sidebar-collapsed #sidebar-collapse-btn svg { transform: rotate(180deg); }

/* Tooltip on collapsed nav items */
body.sidebar-collapsed .nav-item {
  justify-content: center;
  padding: 0.55rem;
  position: relative;
}
body.sidebar-collapsed .nav-item::after {
  content: attr(data-tooltip);
  position: absolute;
  left: calc(var(--sidebar-collapsed-w) + 8px);
  top: 50%;
  transform: translateY(-50%);
  background: #2a2f3a;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 10px;
  font-size: 0.8rem;
  white-space: nowrap;
  color: var(--text);
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.12s;
  z-index: 300;
}
body.sidebar-collapsed .nav-item:hover::after { opacity: 1; }