/* ─── Sidebar Overlay — Soft Dim ─── */
#sidebarOverlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,.3);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--anim-slow);
  z-index: 2500;
  backdrop-filter: blur(4px);
}

#sidebarOverlay.show {
  opacity: 1;
  pointer-events: auto;
}

/* ─── Sidebar Body — Monolithic Neumorphic Surface ─── */
#sidebar {
  position: fixed;
  top: var(--appbar-h);
  left: 0;
  height: calc(100% - var(--appbar-h));
  width: min(86vw, 280px);
  background: var(--surface);
  border-right: 1px solid rgba(0,0,0,0.02);
  padding: 16px 12px;
  overflow-y: auto;
  overflow-x: clip;
  transform: translateX(-105%);
  transition: width var(--nm-anim), transform var(--nm-anim);
  z-index: 2600;
  box-shadow: 10px 0 20px rgba(0,0,0,0.02);
  display: flex;
  flex-direction: column;
}

#sidebar.drawer.show {
  transform: translateX(0);
}

/* Desktop: sticky sidebar */
@media (min-width: 900px) {
  #sidebar {
    position: sticky;
    top: var(--appbar-h);
    height: calc(100vh - var(--appbar-h));
    width: var(--sidebar-w);
    transform: none;
    box-shadow: none;
  }

  #sidebar.collapsed {
    width: var(--sidebar-w-collapsed);
  }

  #sidebar.collapsed .sidebar-title,
  #sidebar.collapsed .nav-text,
  #sidebar.collapsed .sidebar__chxd-toggle-text,
  #sidebar.collapsed .sidebar__chxd-chevron {
    display: none;
  }

  #sidebar.collapsed .nav-item {
    justify-content: center;
    padding: 12px 8px;
  }
}

/* ─── Sidebar Header — Soft Title ─── */
.sidebar-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 0 8px 16px;
  margin-bottom: 8px;
  border-bottom: 1px solid rgba(0,0,0,0.03);
}

.sidebar-title {
  font-weight: 800;
  font-size: .75rem;
  color: var(--primary);
  letter-spacing: .1em;
  text-transform: uppercase;
}

#toggleSidebar {
  cursor: pointer;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  color: var(--text-body);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--nm-anim);
  background: var(--surface);
  box-shadow: var(--nm-flat);
}

#toggleSidebar:hover {
  color: var(--primary);
  box-shadow: 2px 2px 5px var(--nm-dark), -2px -2px 5px var(--nm-light);
}

/* ─── Navigation Items — Soft Pill ─── */
.sidebar__nav {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 8px 0;
}

#sidebar .nav-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  cursor: pointer;
  color: var(--text-body);
  border-radius: var(--radius);
  position: relative;
  transition: all var(--nm-anim);
  user-select: none;
  background: transparent;
  border: none; /* Đảm bảo button nav-item không có border */
  text-align: left;
  width: 100%;
}

#sidebar .nav-item:hover {
  background: var(--surface);
  box-shadow: var(--nm-flat);
  color: var(--primary);
  transform: translateX(4px);
}

#sidebar .nav-item.active {
  background: var(--surface);
  box-shadow: var(--nm-inset);
  color: var(--primary);
  font-weight: 800;
}

#sidebar .nav-icon {
  font-size: 1.25rem;
  color: var(--primary);
  opacity: 0.8;
}

#sidebar .nav-item.active .nav-icon {
  opacity: 1;
}

/* ─── Sidebar CHXD Section (Tích hợp trong Nav) ─── */
.sidebar__chxd-toggle {
  margin-top: 16px; /* Thay margin-top: auto bằng khoảng cách cố định để xóa Gap */
  font-weight: 800;
  font-size: 0.8rem;
}

.sidebar__chxd-toggle.is-active {
  box-shadow: var(--nm-inset);
  color: var(--primary);
}

.sidebar__chxd-chevron {
  transition: transform var(--nm-anim);
}

.sidebar__chxd-toggle.is-active .sidebar__chxd-chevron {
  transform: rotate(180deg);
}

.sidebar__chxd-list {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin: 4px 8px 12px;
  max-height: 280px;
  overflow-y: auto;
  padding: 8px;
  background: var(--surface);
  box-shadow: var(--nm-inset);
  border-radius: var(--radius);
}

.sidebar__chxd-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  color: var(--text-body);
  font-size: 0.8125rem;
  font-weight: 600;
  transition: all var(--nm-anim);
}

.sidebar__chxd-item:hover {
  background: rgba(var(--primary-rgb), 0.05);
  color: var(--primary);
  padding-left: 16px;
}

.sidebar__chxd-item.active {
  background: var(--primary);
  color: var(--text-on-brand);
  box-shadow: var(--nm-float);
}

/* Custom Scrollbar for list */
.sidebar__chxd-list::-webkit-scrollbar {
  width: 4px;
}
.sidebar__chxd-list::-webkit-scrollbar-thumb {
  background: var(--border-2);
  border-radius: 4px;
}

/* Desktop: collapsed mode adjustments */
@media (min-width: 900px) {
  #sidebar.collapsed .sidebar__chxd-toggle .nav-text,
  #sidebar.collapsed .sidebar__chxd-chevron {
    display: none;
  }
}

/* Dark mode specific sidebar tweaks */
body.dark #sidebar {
  border-right-color: rgba(255,255,255,0.02);
  box-shadow: 10px 0 20px rgba(0,0,0,0.1);
}

body.dark .sidebar-head {
  border-bottom-color: rgba(255,255,255,0.05);
}