:root {
  /* Material Design 3 Light Mode Palette */
  --admin-bg: #f8fafc;
  --admin-surface: #ffffff;
  --admin-surface-subtle: #f1f5f9;
  --admin-surface-hover: #f8fafc;
  --admin-border: #e2e8f0;
  --admin-border-strong: #cbd5e1;

  --text-main: #0f172a;
  --text-muted: #475569;
  --text-subtle: #94a3b8;
  --text-white: #ffffff;

  --primary: #1a73e8;
  --primary-hover: #1557b0;
  --primary-light: #eff6ff;
  --primary-border: #bfdbfe;

  --success: #16a34a;
  --success-bg: #f0fdf4;
  --success-border: #bbf7d0;

  --warning: #d97706;
  --warning-bg: #fffbeb;
  --warning-border: #fde68a;

  --danger: #dc2626;
  --danger-bg: #fef2f2;
  --danger-border: #fecaca;

  --info: #0284c7;
  --info-bg: #f0f9ff;
  --info-border: #bae6fd;

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;

  /* Shadows */
  --shadow-xs: 0 1px 2px 0 rgba(15, 23, 42, 0.05);
  --shadow-sm: 0 1px 3px 0 rgba(15, 23, 42, 0.08), 0 1px 2px -1px rgba(15, 23, 42, 0.04);
  --shadow-md: 0 4px 6px -1px rgba(15, 23, 42, 0.08), 0 2px 4px -2px rgba(15, 23, 42, 0.04);
  --shadow-lg: 0 10px 15px -3px rgba(15, 23, 42, 0.09), 0 4px 6px -4px rgba(15, 23, 42, 0.04);
  --shadow-dialog: 0 20px 25px -5px rgba(15, 23, 42, 0.12), 0 8px 10px -6px rgba(15, 23, 42, 0.05);

  /* Radius */
  --r-xs: 4px;
  --r-sm: 6px;
  --r-md: 8px;
  --r-lg: 12px;
  --r-xl: 16px;
  --r-full: 9999px;

  --sidebar-width: 256px;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html, body {
  height: 100%;
  font-family: var(--font-sans);
  background-color: var(--admin-bg);
  color: var(--text-main);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

/* ──────────────────────────────────────────
   App Layout
   ────────────────────────────────────────── */
.admin-layout {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* Sidebar */
.admin-sidebar {
  width: var(--sidebar-width);
  background: var(--admin-surface);
  border-right: 1px solid var(--admin-border);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  user-select: none;
}

.sidebar-header {
  height: 64px;
  padding: 0 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--admin-border);
}

.sidebar-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--text-main);
  text-decoration: none;
}

.sidebar-brand img {
  width: 28px;
  height: 28px;
}

.sidebar-status-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 8px;
  background: var(--success-bg);
  border: 1px solid var(--success-border);
  color: var(--success);
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: var(--r-full);
}

.sidebar-status-pill .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--success);
}

.sidebar-nav {
  flex: 1;
  overflow-y: auto;
  padding: 14px 10px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.nav-section-title {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--text-subtle);
  letter-spacing: 0.06em;
  padding: 12px 10px 4px;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 12px;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
  border-radius: var(--r-md);
  text-decoration: none;
  cursor: pointer;
  transition: all 0.15s ease;
}

.nav-item:hover {
  background: var(--admin-surface-subtle);
  color: var(--text-main);
}

.nav-item.active {
  background: var(--primary-light);
  color: var(--primary);
  font-weight: 600;
}

.nav-item svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.nav-badge {
  margin-left: auto;
  padding: 1px 7px;
  font-size: 0.72rem;
  font-weight: 600;
  border-radius: var(--r-full);
  background: var(--admin-surface-subtle);
  color: var(--text-muted);
}

.nav-item.active .nav-badge {
  background: var(--primary);
  color: #ffffff;
}

.nav-badge.danger {
  background: var(--danger-bg);
  color: var(--danger);
}

.sidebar-footer {
  padding: 12px 14px;
  border-top: 1px solid var(--admin-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--admin-surface-subtle);
}

.supervisor-profile {
  display: flex;
  align-items: center;
  gap: 10px;
  overflow: hidden;
}

.supervisor-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--primary);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 0.8rem;
  flex-shrink: 0;
}

.supervisor-meta {
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.supervisor-name {
  font-size: 0.825rem;
  font-weight: 600;
  color: var(--text-main);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.supervisor-role {
  font-size: 0.7rem;
  color: var(--primary);
  font-weight: 600;
}

/* Main Container */
.admin-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: var(--admin-bg);
  overflow: hidden;
}

/* Topbar */
.admin-topbar {
  height: 64px;
  background: var(--admin-surface);
  border-bottom: 1px solid var(--admin-border);
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-shrink: 0;
}

.topbar-left {
  display: flex;
  align-items: center;
  gap: 14px;
}

.topbar-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
  letter-spacing: -0.015em;
}

.topbar-subtitle {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.topbar-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

/* Content Area */
.admin-content {
  flex: 1;
  overflow-y: auto;
  padding: 24px;
}

/* ──────────────────────────────────────────
   Material Components & Elements
   ────────────────────────────────────────── */

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 500;
  padding: 7px 14px;
  border-radius: var(--r-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.15s ease;
  line-height: 1.25;
  white-space: nowrap;
}

.btn:active {
  transform: scale(0.98);
}

.btn-sm {
  padding: 4px 10px;
  font-size: 0.775rem;
  border-radius: var(--r-sm);
}

.btn-primary {
  background: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
  box-shadow: var(--shadow-xs);
}

.btn-primary:hover {
  background: var(--primary-hover);
  border-color: var(--primary-hover);
}

.btn-secondary {
  background: var(--admin-surface);
  color: var(--text-main);
  border-color: var(--admin-border-strong);
  box-shadow: var(--shadow-xs);
}

.btn-secondary:hover {
  background: var(--admin-surface-subtle);
  border-color: var(--text-subtle);
}

.btn-danger {
  background: var(--danger);
  color: #ffffff;
  border-color: var(--danger);
}

.btn-danger:hover {
  background: #b91c1c;
}

.btn-success {
  background: var(--success);
  color: #ffffff;
  border-color: var(--success);
}

.btn-success:hover {
  background: #15803d;
}

.btn-tonal {
  background: var(--primary-light);
  color: var(--primary);
  border-color: var(--primary-border);
}

.btn-tonal:hover {
  background: #dbeafe;
}

.btn-icon {
  width: 32px;
  height: 32px;
  padding: 0;
  border-radius: var(--r-md);
  background: var(--admin-surface);
  border: 1px solid var(--admin-border);
  color: var(--text-muted);
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.btn-icon:hover {
  background: var(--admin-surface-subtle);
  color: var(--text-main);
}

/* Cards */
.card {
  background: var(--admin-surface);
  border: 1px solid var(--admin-border);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}

.card-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--admin-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.card-title {
  font-size: 0.975rem;
  font-weight: 600;
  color: var(--text-main);
}

.card-body {
  padding: 20px;
}

/* Stat Cards Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-bottom: 24px;
}

.stat-card {
  background: var(--admin-surface);
  border: 1px solid var(--admin-border);
  border-radius: var(--r-lg);
  padding: 18px 20px;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  position: relative;
}

.stat-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
}

.stat-title {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.stat-icon {
  width: 32px;
  height: 32px;
  border-radius: var(--r-md);
  background: var(--primary-light);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
}

.stat-value {
  font-size: 1.85rem;
  font-weight: 700;
  color: var(--text-main);
  letter-spacing: -0.02em;
  line-height: 1.1;
}

.stat-detail {
  font-size: 0.775rem;
  color: var(--text-muted);
  margin-top: 6px;
}

/* Tables */
.table-container {
  overflow-x: auto;
  border-radius: var(--r-lg);
  border: 1px solid var(--admin-border);
  background: var(--admin-surface);
  box-shadow: var(--shadow-sm);
}

.table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.85rem;
}

.table th {
  background: var(--admin-surface-subtle);
  padding: 12px 16px;
  font-weight: 600;
  color: var(--text-muted);
  border-bottom: 1px solid var(--admin-border);
  white-space: nowrap;
}

.table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--admin-border);
  color: var(--text-main);
  vertical-align: middle;
}

.table tr:last-child td {
  border-bottom: none;
}

.table tr:hover td {
  background: var(--admin-surface-hover);
}

/* Badges / Chips */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 8px;
  font-size: 0.725rem;
  font-weight: 600;
  border-radius: var(--r-full);
  line-height: 1.3;
}

.badge-primary {
  background: var(--primary-light);
  color: var(--primary);
  border: 1px solid var(--primary-border);
}

.badge-success {
  background: var(--success-bg);
  color: var(--success);
  border: 1px solid var(--success-border);
}

.badge-warning {
  background: var(--warning-bg);
  color: var(--warning);
  border: 1px solid var(--warning-border);
}

.badge-danger {
  background: var(--danger-bg);
  color: var(--danger);
  border: 1px solid var(--danger-border);
}

.badge-neutral {
  background: var(--admin-surface-subtle);
  color: var(--text-muted);
  border: 1px solid var(--admin-border);
}

/* Forms & Inputs */
.form-group {
  margin-bottom: 16px;
}

.form-label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 6px;
}

.form-control {
  width: 100%;
  padding: 8px 12px;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  color: var(--text-main);
  background: var(--admin-surface);
  border: 1px solid var(--admin-border-strong);
  border-radius: var(--r-md);
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.form-control:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.15);
}

textarea.form-control {
  min-height: 80px;
  resize: vertical;
}

.search-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--admin-surface);
  border: 1px solid var(--admin-border);
  border-radius: var(--r-md);
  padding: 4px 12px;
  min-width: 260px;
}

.search-bar input {
  border: none;
  background: transparent;
  outline: none;
  font-size: 0.85rem;
  color: var(--text-main);
  width: 100%;
}

/* Modals */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.4);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2000;
  padding: 20px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
}

.modal-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.modal {
  background: var(--admin-surface);
  border: 1px solid var(--admin-border);
  border-radius: var(--r-xl);
  box-shadow: var(--shadow-dialog);
  width: 100%;
  max-width: 640px;
  max-height: 90vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transform: translateY(10px);
  transition: transform 0.2s ease;
}

.modal-overlay.active .modal {
  transform: translateY(0);
}

.modal-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--admin-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
}

.modal-body {
  padding: 20px;
  overflow-y: auto;
}

.modal-footer {
  padding: 14px 20px;
  border-top: 1px solid var(--admin-border);
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
  background: var(--admin-surface-subtle);
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 3000;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.toast {
  background: var(--admin-surface);
  border: 1px solid var(--admin-border);
  border-radius: var(--r-md);
  box-shadow: var(--shadow-lg);
  padding: 12px 18px;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.85rem;
  color: var(--text-main);
  min-width: 280px;
  animation: toastSlideIn 0.25s ease forwards;
}

@keyframes toastSlideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

.toast.success {
  border-left: 4px solid var(--success);
}

.toast.error {
  border-left: 4px solid var(--danger);
}

.toast.info {
  border-left: 4px solid var(--primary);
}

/* User avatar pill */
.user-cell {
  display: flex;
  align-items: center;
  gap: 10px;
}

.user-cell-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: #e2e8f0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 0.775rem;
  color: var(--text-muted);
  flex-shrink: 0;
  overflow: hidden;
}

.user-cell-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* SQL Console */
.sql-editor {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  background: #ffffff;
  border: 1px solid var(--admin-border-strong);
  border-radius: var(--r-md);
  padding: 12px;
  min-height: 120px;
  width: 100%;
  outline: none;
}

.sql-editor:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.15);
}

/* Empty State */
.empty-state {
  text-align: center;
  padding: 48px 20px;
  color: var(--text-subtle);
}

.empty-state svg {
  width: 48px;
  height: 48px;
  margin-bottom: 12px;
  color: var(--text-subtle);
}

.empty-state h4 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 6px;
}

.empty-state p {
  font-size: 0.85rem;
  color: var(--text-muted);
}