/* ── Sidebar ── */
.sidebar {
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--sidebar-bg);
  border-left: 1px solid var(--sidebar-border);
  display: flex;
  flex-direction: column;
  position: fixed;
  right: 0; top: 0; bottom: 0;
  z-index: var(--z-above);
  transition: width var(--transition-base), transform var(--transition-base);
  overflow: hidden;
}
.sidebar.collapsed { width: var(--sidebar-collapsed); }

/* Header */
.sidebar-header {
  height: var(--topbar-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-4);
  border-bottom: 1px solid var(--sidebar-border);
  flex-shrink: 0;
  gap: var(--space-2);
}
.sidebar-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  overflow: hidden;
  min-width: 0;
}
.sidebar-logo-mark {
  width: 38px; height: 38px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--blue-600), var(--sky-400));
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
  box-shadow: 0 4px 12px rgba(37,99,235,.3);
}
.sidebar-brand {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transition: opacity var(--transition-base), width var(--transition-base);
  min-width: 0;
}
.sidebar-app-name {
  font-size: var(--text-sm);
  font-weight: var(--font-weight-black);
  color: var(--color-text);
  white-space: nowrap;
  letter-spacing: -0.02em;
  line-height: 1.2;
}
.sidebar-app-sub {
  font-size: 10px;
  color: var(--color-text-muted);
  white-space: nowrap;
  font-weight: var(--font-weight-normal);
}
.sidebar.collapsed .sidebar-brand { opacity: 0; width: 0; pointer-events: none; }

.sidebar-collapse-btn {
  width: 30px; height: 30px;
  border-radius: var(--radius-sm);
  display: flex; align-items: center; justify-content: center;
  color: var(--color-text-subtle);
  cursor: pointer;
  border: 1px solid var(--color-border);
  background: var(--color-surface-2);
  flex-shrink: 0;
  transition: all var(--transition-fast);
}
.sidebar-collapse-btn:hover { color: var(--color-primary); border-color: var(--color-primary); }
.sidebar-collapse-btn svg { transition: transform var(--transition-base); }
.sidebar.collapsed .sidebar-collapse-btn svg { transform: rotate(180deg); }

/* Nav */
.sidebar-nav {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  padding: var(--space-3) var(--space-2);
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.sidebar-nav-item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: 10px var(--space-3);
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  font-weight: var(--font-weight-semi);
  text-decoration: none;
  transition: all var(--transition-fast);
  cursor: pointer;
  white-space: nowrap;
  overflow: hidden;
  position: relative;
}
.sidebar-nav-item:hover {
  background: var(--color-primary-bg);
  color: var(--color-primary);
}
.sidebar-nav-item.active {
  background: var(--color-primary-muted);
  color: var(--color-primary);
  font-weight: var(--font-weight-bold);
}
.sidebar-nav-item.active::after {
  content: '';
  position: absolute;
  inset-inline-end: 0;
  top: 25%; bottom: 25%;
  width: 3px;
  background: var(--color-primary);
  border-radius: var(--radius-full) 0 0 var(--radius-full);
}
.sidebar-nav-icon {
  width: 20px; height: 20px;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
  opacity: 0.85;
}
.sidebar-nav-item.active .sidebar-nav-icon,
.sidebar-nav-item:hover .sidebar-nav-icon { opacity: 1; }
.sidebar-nav-label {
  flex: 1;
  transition: opacity var(--transition-base);
  overflow: hidden;
}
.sidebar.collapsed .sidebar-nav-label { opacity: 0; pointer-events: none; }

/* Collapsed tooltip */
.sidebar.collapsed .sidebar-nav-item {
  justify-content: center;
  padding-inline: 0;
}
.sidebar.collapsed .sidebar-nav-item::before {
  content: attr(title);
  position: absolute;
  right: calc(100% + 10px);
  top: 50%; transform: translateY(-50%);
  background: var(--slate-900);
  color: #fff;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  font-size: var(--text-xs);
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-fast);
  z-index: var(--z-tooltip);
}
.sidebar.collapsed .sidebar-nav-item:hover::before { opacity: 1; }
[data-theme="dark"] .sidebar.collapsed .sidebar-nav-item::before { background: var(--slate-700); }

/* Footer */
.sidebar-footer {
  padding: var(--space-3) var(--space-3);
  border-top: 1px solid var(--sidebar-border);
  display: flex;
  align-items: center;
  gap: var(--space-2);
  flex-shrink: 0;
}
.sidebar-user {
  display: flex; align-items: center;
  gap: var(--space-3);
  flex: 1; overflow: hidden; min-width: 0;
}
.sidebar-user-info {
  display: flex; flex-direction: column;
  overflow: hidden;
  transition: opacity var(--transition-base), width var(--transition-base);
}
.sidebar-user-name {
  font-size: var(--text-sm);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
  white-space: nowrap;
}
.sidebar-user-role {
  font-size: 10px;
  color: var(--color-text-muted);
  white-space: nowrap;
}
.sidebar.collapsed .sidebar-user-info { opacity: 0; width: 0; pointer-events: none; }
.sidebar-logout-btn {
  width: 32px; height: 32px;
  border-radius: var(--radius-sm);
  display: flex; align-items: center; justify-content: center;
  color: var(--color-text-subtle);
  cursor: pointer; border: none; background: none;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}
.sidebar-logout-btn:hover { color: var(--danger); background: rgba(239,68,68,.1); }
.sidebar.collapsed .sidebar-logout-btn { opacity: 0; pointer-events: none; }

/* Overlay */
.sidebar-overlay {
  display: none;
  position: fixed; inset: 0;
  background: rgba(7,13,26,.5);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: calc(var(--z-above) - 1);
  opacity: 0;
  transition: opacity var(--transition-base);
}
.sidebar-overlay.active { opacity: 1; }

/* Topbar */
.topbar {
  height: var(--topbar-height);
  background: var(--topbar-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-border-light);
  position: sticky; top: 0;
  z-index: var(--z-above);
  display: flex; align-items: center;
  padding: 0 var(--space-6);
  gap: var(--space-4);
}
.topbar-title {
  font-size: var(--text-lg);
  font-weight: var(--font-weight-bold);
  color: var(--color-text);
  flex: 1;
}
.topbar-menu-btn {
  width: 38px; height: 38px;
  border-radius: var(--radius-md);
  display: flex; align-items: center; justify-content: center;
  color: var(--color-text-muted);
  cursor: pointer; border: none; background: none;
  transition: all var(--transition-fast);
}
.topbar-menu-btn:hover { background: var(--color-surface-2); color: var(--color-text); }
.topbar-actions { display: flex; align-items: center; gap: var(--space-1); }
.topbar-btn {
  width: 38px; height: 38px;
  border-radius: var(--radius-md);
  display: flex; align-items: center; justify-content: center;
  color: var(--color-text-muted);
  cursor: pointer; border: none; background: none;
  transition: all var(--transition-fast);
  position: relative;
}
.topbar-btn:hover { background: var(--color-surface-2); color: var(--color-primary); }
.icon-sun, .icon-moon {
  display: flex; align-items: center; justify-content: center;
}

/* Mobile Bottom Nav */
.mobile-nav {
  display: none;
  position: fixed; bottom: 0; left: 0; right: 0;
  height: var(--mobile-nav-height);
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  z-index: var(--z-above);
  padding-bottom: env(safe-area-inset-bottom);
  align-items: stretch;
  justify-content: space-around;
}
.mobile-nav-item {
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  gap: 3px; flex: 1; padding: var(--space-2);
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color var(--transition-fast);
  position: relative;
}
.mobile-nav-item.active { color: var(--color-primary); }
.mobile-nav-item.active::before {
  content: '';
  position: absolute; top: 0; left: 20%; right: 20%;
  height: 2px;
  background: var(--color-primary);
  border-radius: 0 0 var(--radius-full) var(--radius-full);
}
.mobile-nav-icon {
  display: flex; align-items: center; justify-content: center;
}
.mobile-nav-label { font-size: 10px; font-weight: var(--font-weight-semi); }

/* Responsive */
@media (max-width: 1024px) {
  .sidebar-overlay { display: block; pointer-events: none; }
  .sidebar-overlay.active { pointer-events: all; }
  .sidebar { transform: translateX(110%); box-shadow: var(--shadow-xl); }
  .sidebar.open { transform: translateX(0); }
  .main-content { margin-right: 0 !important; }
  .topbar { padding: 0 var(--space-4); }
}
@media (max-width: 640px) {
  .mobile-nav { display: flex; }
  .page-content { padding-bottom: calc(var(--mobile-nav-height) + var(--space-4)); }
}