/* ============================================================
   Holiday Checker – CSS Design System
   ============================================================ */

/* ---------- Custom properties (Light theme) ---------- */
:root {
  --bg-primary: #ffffff;
  --bg-secondary: #f4f6f8;
  --bg-card: #ffffff;
  --bg-input: #f4f6f8;
  --bg-hover: #edf0f3;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --accent: #0c6e4f;
  --accent-light: #e6f5ef;
  --accent-hover: #0a5a40;
  --border: #e2e8f0;
  --border-strong: #cbd5e1;
  --danger: #dc2626;
  --danger-light: #fef2f2;
  --success: #16a34a;
  --success-light: #f0fdf4;
  --warning: #ea580c;
  --warning-light: #fff7ed;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.08);
  --radius: 10px;
  --radius-sm: 6px;
  --radius-lg: 16px;
  --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", monospace;
  --transition: 0.2s ease;
}

/* ---------- Dark theme ---------- */
[data-theme="dark"] {
  --bg-primary: #0b0f19;
  --bg-secondary: #111827;
  --bg-card: #151c2c;
  --bg-input: #1e2740;
  --bg-hover: #1e2740;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent: #22c986;
  --accent-light: #0f2d22;
  --accent-hover: #34d89a;
  --border: #1e293b;
  --border-strong: #334155;
  --danger: #ef4444;
  --danger-light: #2d1515;
  --success: #22c55e;
  --success-light: #0f2d1a;
  --warning: #f97316;
  --warning-light: #2d1b0f;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.4);
}

/* ---------- Reset & base ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  transition: background var(--transition), color var(--transition);
  min-height: 100vh;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

img {
  max-width: 100%;
  display: block;
}

/* ---------- Typography ---------- */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-primary);
  text-wrap: balance;
}

h1 { font-size: 2.25rem; letter-spacing: -0.025em; }
h2 { font-size: 1.75rem; letter-spacing: -0.02em; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.1rem; }

p { color: var(--text-secondary); }

/* ---------- Layout ---------- */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 4rem 0;
}

.section-header {
  text-align: center;
  margin-bottom: 3rem;
}

.section-header p {
  margin-top: 0.5rem;
  font-size: 1.05rem;
}

/* ---------- Header / Navbar ---------- */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.navbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 1.5rem;
  max-width: 1200px;
  margin: 0 auto;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.navbar-brand svg {
  color: var(--accent);
}

.navbar-nav {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
}

.navbar-nav a {
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition);
}

.navbar-nav a:hover,
.navbar-nav a.active {
  color: var(--text-primary);
  background: var(--bg-hover);
  text-decoration: none;
}

.navbar-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.hamburger {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  padding: 0.5rem;
  border-radius: var(--radius-sm);
}

.hamburger:hover {
  background: var(--bg-hover);
}

/* ---------- Theme toggle ---------- */
.theme-toggle {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.25rem;
  cursor: pointer;
}

.theme-toggle-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  border-radius: 999px;
  border: none;
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition);
}

.theme-toggle-btn.active {
  background: var(--bg-card);
  color: var(--text-primary);
  box-shadow: var(--shadow-sm);
}

.theme-toggle-btn svg {
  width: 16px;
  height: 16px;
}

/* ---------- Cards ---------- */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  transition: all var(--transition);
  box-shadow: var(--shadow-sm);
}

.card:hover {
  box-shadow: var(--shadow-md);
}

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border);
}

.card-header h3 {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* ---------- Hero section ---------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: 5rem 0 4rem;
  text-align: center;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 50% 0%, var(--accent-light) 0%, transparent 70%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 1rem;
  letter-spacing: -0.03em;
}

.hero p {
  font-size: 1.15rem;
  max-width: 600px;
  margin: 0 auto 2rem;
}

.hero-status {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.25rem 2rem;
  box-shadow: var(--shadow-md);
  margin-bottom: 1.5rem;
}

.status-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  animation: pulse 2s infinite;
}

.status-dot.holiday {
  background: var(--success);
}

.status-dot.workday {
  background: var(--text-muted);
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.hero-status .status-text {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-primary);
}

.hero-status .status-sub {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.hero-country-select {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  margin-top: 1.5rem;
  flex-wrap: wrap;
}

/* ---------- Next holiday card ---------- */
.next-holiday-card {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  background: var(--accent-light);
  border: 1px solid var(--accent);
  border-radius: var(--radius-lg);
  padding: 1.25rem 1.5rem;
  margin-top: 1.5rem;
  max-width: 520px;
  margin-left: auto;
  margin-right: auto;
}

.next-holiday-card .countdown-number {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
  min-width: 60px;
  text-align: center;
}

.next-holiday-card .countdown-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  font-weight: 600;
}

.next-holiday-card .holiday-info h4 {
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.next-holiday-card .holiday-info p {
  font-size: 0.85rem;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 600;
  font-family: var(--font-sans);
  cursor: pointer;
  border: 1px solid transparent;
  transition: all var(--transition);
  white-space: nowrap;
  text-decoration: none;
}

.btn:hover {
  text-decoration: none;
}

.btn svg {
  width: 16px;
  height: 16px;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff;
}

.btn-secondary {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border-color: var(--border);
}

.btn-secondary:hover {
  background: var(--bg-hover);
  border-color: var(--border-strong);
}

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

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

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
}

.btn-ghost:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.btn-sm {
  padding: 0.4rem 0.75rem;
  font-size: 0.8rem;
}

.btn-lg {
  padding: 0.75rem 1.75rem;
  font-size: 1rem;
}

/* ---------- Forms ---------- */
.form-group {
  margin-bottom: 1.25rem;
}

.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.375rem;
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 0.625rem 0.875rem;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-family: var(--font-sans);
  color: var(--text-primary);
  transition: all var(--transition);
  outline: none;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(12, 110, 79, 0.12);
}

.form-textarea {
  min-height: 100px;
  resize: vertical;
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
}

.form-hint {
  font-size: 0.775rem;
  color: var(--text-muted);
  margin-top: 0.25rem;
}

/* ---------- Tabs ---------- */
.tabs {
  display: flex;
  border-bottom: 1px solid var(--border);
  margin-bottom: 1.5rem;
  overflow-x: auto;
}

.tab-btn {
  padding: 0.75rem 1.25rem;
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.tab-btn:hover {
  color: var(--text-secondary);
}

.tab-btn.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
}

/* ---------- Badge ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.2rem 0.6rem;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 600;
}

.badge-success {
  background: var(--success-light);
  color: var(--success);
}

.badge-warning {
  background: var(--warning-light);
  color: var(--warning);
}

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

.badge-accent {
  background: var(--accent-light);
  color: var(--accent);
}

.badge-muted {
  background: var(--bg-secondary);
  color: var(--text-muted);
}

/* ---------- Calendar grid ---------- */
.calendar-grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 2px;
  margin-top: 0.5rem;
}

.calendar-header-cell {
  text-align: center;
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.5rem 0;
  color: var(--text-muted);
}

.calendar-cell {
  aspect-ratio: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 500;
  transition: all var(--transition);
  cursor: default;
  position: relative;
  min-height: 36px;
}

.calendar-cell.empty {
  opacity: 0;
}

.calendar-cell.today {
  background: var(--accent);
  color: #fff;
  font-weight: 700;
}

.calendar-cell.holiday {
  background: var(--success-light);
  color: var(--success);
  font-weight: 700;
}

.calendar-cell.weekend {
  color: var(--text-muted);
}

.calendar-cell.leave {
  background: var(--warning-light);
  color: var(--warning);
  font-weight: 700;
}

.calendar-cell.bridge {
  background: #ede9fe;
  color: #7c3aed;
  font-weight: 700;
}

[data-theme="dark"] .calendar-cell.bridge {
  background: #1e1542;
  color: #a78bfa;
}

.calendar-cell:hover:not(.empty) {
  box-shadow: var(--shadow-sm);
  transform: scale(1.05);
}

.calendar-cell .dot {
  width: 4px;
  height: 4px;
  border-radius: 50%;
  margin-top: 2px;
}

.calendar-cell .dot.holiday-dot { background: var(--success); }
.calendar-cell .dot.leave-dot { background: var(--warning); }

/* ---------- Month grid (yearly calendar) ---------- */
.year-calendar {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.month-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem;
}

.month-card h4 {
  text-align: center;
  margin-bottom: 0.5rem;
  font-size: 0.95rem;
}

/* ---------- Tables ---------- */
.table-wrapper {
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

table {
  width: 100%;
  border-collapse: collapse;
}

thead th {
  background: var(--bg-secondary);
  padding: 0.75rem 1rem;
  text-align: left;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-bottom: 1px solid var(--border);
}

tbody td {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border);
  font-size: 0.875rem;
}

tbody tr:hover {
  background: var(--bg-hover);
}

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

/* ---------- Grid layout helpers ---------- */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

/* ---------- Stat cards ---------- */
.stat-card {
  text-align: center;
  padding: 1.5rem;
}

.stat-card .stat-value {
  font-size: 2rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1;
  margin-bottom: 0.375rem;
}

.stat-card .stat-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
}

/* ---------- Result box ---------- */
.result-box {
  background: var(--accent-light);
  border: 1px solid var(--accent);
  border-radius: var(--radius);
  padding: 1.25rem;
  margin-top: 1rem;
}

.result-box .result-value {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--accent);
}

.result-box .result-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* ---------- Tooltip ---------- */
[data-tooltip] {
  position: relative;
}

[data-tooltip]::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: calc(100% + 6px);
  left: 50%;
  transform: translateX(-50%);
  padding: 0.375rem 0.625rem;
  background: var(--text-primary);
  color: var(--bg-primary);
  font-size: 0.75rem;
  border-radius: var(--radius-sm);
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
  z-index: 50;
}

[data-tooltip]:hover::after {
  opacity: 1;
}

/* ---------- Modal ---------- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 200;
  padding: 1rem;
}

.modal-overlay.active {
  display: flex;
}

.modal {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  max-width: 560px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-lg);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border);
}

.modal-header h3 {
  font-size: 1.1rem;
}

.modal-body {
  padding: 1.5rem;
}

.modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: 0.5rem;
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--border);
}

/* ---------- Toast ---------- */
.toast-container {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  z-index: 300;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.toast {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.875rem 1.25rem;
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-width: 280px;
  animation: slideIn 0.3s ease;
  font-size: 0.875rem;
}

.toast.success { border-left: 3px solid var(--success); }
.toast.error { border-left: 3px solid var(--danger); }
.toast.info { border-left: 3px solid var(--accent); }

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

/* ---------- Footer ---------- */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  padding: 3rem 0 1.5rem;
  margin-top: 4rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-brand p {
  font-size: 0.85rem;
  margin-top: 0.5rem;
}

.footer-col h4 {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 0.375rem;
}

.footer-col a {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.footer-col a:hover {
  color: var(--accent);
}

.footer-bottom {
  border-top: 1px solid var(--border);
  padding-top: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ---------- Page styles (privacy, terms) ---------- */
.page-content {
  padding: 3rem 0;
}

.page-content h1 {
  margin-bottom: 0.5rem;
}

.page-content h2 {
  margin-top: 2rem;
  margin-bottom: 0.75rem;
  font-size: 1.35rem;
}

.page-content h3 {
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
}

.page-content p,
.page-content li {
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
}

.page-content ul,
.page-content ol {
  margin-left: 1.5rem;
  margin-bottom: 1rem;
}

.page-content .last-updated {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
}

/* ---------- Export view select ---------- */
.export-controls {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-bottom: 1.5rem;
}

/* ---------- Leave optimizer result ---------- */
.optimizer-summary {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.optimizer-tip {
  background: var(--accent-light);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 1rem 1.25rem;
  margin-bottom: 1.5rem;
}

.optimizer-tip h4 {
  margin-bottom: 0.5rem;
  color: var(--accent);
}

.optimizer-tip p {
  font-size: 0.875rem;
}

/* ---------- Legend ---------- */
.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 1rem;
  margin-bottom: 0.5rem;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.legend-color {
  width: 14px;
  height: 14px;
  border-radius: 3px;
}

/* ---------- Admin panel ---------- */
.admin-layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  min-height: 100vh;
}

.admin-sidebar {
  background: var(--bg-secondary);
  border-right: 1px solid var(--border);
  padding: 1.5rem 0;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}

.admin-sidebar .brand {
  padding: 0 1.25rem 1.25rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 1rem;
}

.admin-sidebar .brand h3 {
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.admin-sidebar .brand p {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.admin-nav {
  list-style: none;
  padding: 0 0.75rem;
}

.admin-nav li a {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.625rem 0.75rem;
  border-radius: var(--radius);
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: all var(--transition);
  font-weight: 500;
}

.admin-nav li a:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
  text-decoration: none;
}

.admin-nav li a.active {
  background: var(--accent-light);
  color: var(--accent);
}

.admin-nav li a svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.admin-main {
  padding: 2rem;
  overflow-y: auto;
}

.admin-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.5rem;
}

/* ---------- Empty state ---------- */
.empty-state {
  text-align: center;
  padding: 3rem 1.5rem;
  color: var(--text-muted);
}

.empty-state svg {
  width: 48px;
  height: 48px;
  margin: 0 auto 1rem;
  color: var(--text-muted);
  opacity: 0.5;
}

/* ---------- Spinner ---------- */
.spinner {
  width: 20px;
  height: 20px;
  border: 2px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  h1 { font-size: 1.75rem; }
  h2 { font-size: 1.35rem; }
  .hero h1 { font-size: 2rem; }
  .hero { padding: 3rem 0 2.5rem; }

  .navbar-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 0.5rem;
  }

  .navbar-nav.open {
    display: flex;
  }

  .hamburger { display: block; }

  .grid-2,
  .grid-3 { grid-template-columns: 1fr; }

  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; gap: 0.5rem; text-align: center; }

  .admin-layout { grid-template-columns: 1fr; }
  .admin-sidebar {
    position: relative;
    height: auto;
  }

  .year-calendar { grid-template-columns: 1fr 1fr; }
  .form-row { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .hero h1 { font-size: 1.6rem; }
  .year-calendar { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: 1fr; }
  .optimizer-summary { grid-template-columns: 1fr 1fr; }
}

/* ---------- Print ---------- */
@media print {
  .navbar, .footer, .btn, .theme-toggle, .export-controls, .hamburger { display: none !important; }
  body { background: #fff; color: #000; }
  .card { border-color: #ddd; box-shadow: none; }
}

/* Utility: visually hidden for a11y */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- Scrollbar ---------- */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}