/* ===== CSS Variables ===== */
:root {
  --bg-primary: #FDF8F3;
  --bg-card: #FFFFFF;
  --bg-soft: #FAF0E6;
  --bg-tag: #F5EBE0;
  --primary: #7BA098;
  --primary-dark: #5C8077;
  --primary-light: #A8C5BC;
  --primary-bg: #E8F0ED;
  --accent: #E8A87C;
  --accent-light: #F4D8C8;
  --accent-bg: #FDF0E6;
  --text-primary: #4A4A4A;
  --text-secondary: #8B8B8B;
  --text-light: #B0B0B0;
  --success: #81B29A;
  --warning: #E8A87C;
  --danger: #D88573;
  --danger-bg: #FBEEE9;
  --border: #F0E6D9;
  --border-dark: #E0D5C7;
  --shadow: 0 2px 12px rgba(180, 160, 140, 0.12);
  --shadow-hover: 0 6px 24px rgba(180, 160, 140, 0.18);
  --shadow-modal: 0 8px 40px rgba(120, 100, 80, 0.25);
  --radius: 16px;
  --radius-sm: 10px;
  --radius-xs: 8px;
  --transition: all 0.3s ease;
  --max-width: 960px;
}

/* ===== Reset ===== */
* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ===== Header ===== */
.header {
  background: var(--bg-card);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 1px 8px rgba(180, 160, 140, 0.08);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  user-select: none;
}

.logo-icon { font-size: 24px; }
.logo-text {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary-dark);
  letter-spacing: 1px;
}

.nav { display: flex; gap: 4px; }

.nav-btn {
  padding: 8px 16px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 15px;
  border-radius: var(--radius-xs);
  cursor: pointer;
  transition: var(--transition);
}

.nav-btn:hover { background: var(--bg-soft); color: var(--text-primary); }
.nav-btn.active { background: var(--primary-bg); color: var(--primary-dark); font-weight: 600; }

/* ===== Main ===== */
.main {
  flex: 1;
  max-width: var(--max-width);
  width: 100%;
  margin: 0 auto;
  padding: 32px 20px 60px;
}

.view { display: none; animation: fadeIn 0.4s ease; }
.view.active { display: block; }

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ===== Page Intro ===== */
.page-intro { text-align: center; margin-bottom: 32px; }

.page-title {
  font-size: 28px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.page-subtitle {
  font-size: 15px;
  color: var(--text-secondary);
}

/* ===== Week Switcher ===== */
.week-switcher {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-bottom: 24px;
}

.week-btn {
  padding: 8px 18px;
  border: 1px solid var(--border-dark);
  background: var(--bg-card);
  color: var(--text-primary);
  font-size: 14px;
  border-radius: var(--radius-xs);
  cursor: pointer;
  transition: var(--transition);
}

.week-btn:hover:not(:disabled) {
  border-color: var(--primary);
  color: var(--primary-dark);
  background: var(--primary-bg);
}

.week-btn:disabled { opacity: 0.4; cursor: not-allowed; }

.week-label {
  font-size: 17px;
  font-weight: 600;
  color: var(--primary-dark);
  min-width: 80px;
  text-align: center;
}

/* ===== Calendar Table ===== */
.calendar-wrapper {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  overflow-x: auto;
}

.calendar-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 600px;
}

.calendar-table th {
  background: var(--bg-soft);
  padding: 14px 8px;
  font-size: 14px;
  font-weight: 600;
  color: var(--primary-dark);
  border-bottom: 2px solid var(--border);
  white-space: nowrap;
}

.calendar-table th .day-date {
  display: block;
  font-size: 12px;
  font-weight: 400;
  color: var(--text-light);
  margin-top: 2px;
}

.calendar-table th.today-col {
  background: var(--accent-bg);
}

.calendar-table td {
  padding: 6px;
  text-align: center;
  border: 1px solid var(--border);
}

.calendar-table td.period-label {
  background: var(--bg-soft);
  font-weight: 600;
  font-size: 14px;
  color: var(--primary-dark);
  width: 70px;
  white-space: nowrap;
}

/* Slot cells */
.slot {
  width: 100%;
  min-height: 52px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-xs);
  cursor: pointer;
  transition: var(--transition);
  font-size: 13px;
  position: relative;
}

.slot.available {
  background: var(--primary-bg);
  color: var(--primary-dark);
}

.slot.available:hover {
  background: var(--primary-light);
  color: white;
  transform: scale(1.05);
}

.slot.available::after {
  content: '○';
  font-size: 16px;
}

.slot.available:hover::after { content: '预约'; font-size: 13px; }

.slot.pending {
  background: var(--accent-bg);
  color: var(--accent);
  cursor: default;
}

.slot.pending::after { content: '待确认'; }

.slot.booked {
  background: var(--bg-tag);
  color: var(--text-light);
  cursor: default;
}

.slot.booked::after { content: '已约'; }

.slot.mine-pending {
  background: var(--accent-light);
  color: var(--accent);
  cursor: pointer;
}

.slot.mine-pending::after { content: '我的·待确认'; font-size: 12px; }

.slot.mine-confirmed {
  background: var(--primary-light);
  color: white;
  cursor: pointer;
}

.slot.mine-confirmed::after { content: '我的·已确认'; font-size: 12px; }

.slot.past {
  background: var(--bg-tag);
  color: var(--text-light);
  cursor: not-allowed;
  opacity: 0.5;
}

.slot.past::after { content: '—'; }

/* ===== Legend ===== */
.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  justify-content: center;
  margin-top: 20px;
  padding: 16px;
  background: var(--bg-card);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow);
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--text-secondary);
}

.dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  display: inline-block;
}

.dot-available { background: var(--primary-bg); border: 1px solid var(--primary-light); }
.dot-pending { background: var(--accent-bg); border: 1px solid var(--accent); }
.dot-booked { background: var(--bg-tag); border: 1px solid var(--border-dark); }
.dot-mine { background: var(--primary-light); }
.dot-past { background: var(--bg-tag); opacity: 0.5; }

/* ===== Tips Card ===== */
.tips-card {
  margin-top: 24px;
  padding: 24px;
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  border-left: 4px solid var(--accent);
}

.tips-card h3 {
  font-size: 16px;
  color: var(--primary-dark);
  margin-bottom: 12px;
}

.tips-card ul {
  list-style: none;
  padding: 0;
}

.tips-card li {
  padding: 5px 0;
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.8;
  position: relative;
  padding-left: 18px;
}

.tips-card li::before {
  content: '✦';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 12px;
}

.highlight { color: var(--accent); font-weight: 600; }

/* ===== Bookings List ===== */
.bookings-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.booking-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 20px 24px;
  transition: var(--transition);
  border-left: 4px solid var(--border-dark);
}

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

.booking-card.status-pending { border-left-color: var(--accent); }
.booking-card.status-confirmed { border-left-color: var(--success); }
.booking-card.status-cancelled { border-left-color: var(--danger); opacity: 0.65; }

.booking-card-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 14px;
  flex-wrap: wrap;
  gap: 10px;
}

.booking-date-period {
  display: flex;
  align-items: center;
  gap: 12px;
}

.booking-date {
  font-size: 17px;
  font-weight: 600;
  color: var(--text-primary);
}

.booking-period {
  font-size: 14px;
  color: var(--primary-dark);
  background: var(--primary-bg);
  padding: 3px 10px;
  border-radius: 20px;
}

.status-badge {
  padding: 4px 14px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
  white-space: nowrap;
}

.status-badge.pending { background: var(--accent-bg); color: var(--accent); }
.status-badge.confirmed { background: var(--primary-bg); color: var(--success); }
.status-badge.cancelled { background: var(--danger-bg); color: var(--danger); }

.booking-info-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 10px 20px;
  margin-bottom: 14px;
}

.info-item {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.info-label {
  font-size: 12px;
  color: var(--text-light);
}

.info-value {
  font-size: 15px;
  color: var(--text-primary);
}

.screenshot-thumb {
  width: 60px;
  height: 60px;
  object-fit: cover;
  border-radius: var(--radius-xs);
  cursor: pointer;
  border: 2px solid var(--border);
  transition: var(--transition);
}

.screenshot-thumb:hover { border-color: var(--primary); transform: scale(1.05); }

.booking-actions {
  display: flex;
  gap: 10px;
  margin-top: 8px;
}

/* ===== Empty State ===== */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--text-light);
}

.empty-state .empty-icon { font-size: 48px; margin-bottom: 16px; }
.empty-state .empty-text { font-size: 16px; }

/* ===== Admin Stats ===== */
.admin-stats {
  display: flex;
  gap: 16px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.stat-card {
  flex: 1;
  min-width: 120px;
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 20px;
  text-align: center;
  transition: var(--transition);
}

.stat-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-2px); }

.stat-num {
  display: block;
  font-size: 32px;
  font-weight: 700;
  margin-bottom: 4px;
}

.stat-pending .stat-num { color: var(--accent); }
.stat-confirmed .stat-num { color: var(--success); }
.stat-total .stat-num { color: var(--primary-dark); }

.stat-label { font-size: 14px; color: var(--text-secondary); }

/* ===== Admin Filter ===== */
.admin-filter {
  display: flex;
  gap: 8px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 6px 16px;
  border: 1px solid var(--border-dark);
  background: var(--bg-card);
  color: var(--text-secondary);
  font-size: 14px;
  border-radius: 20px;
  cursor: pointer;
  transition: var(--transition);
}

.filter-btn:hover { border-color: var(--primary); color: var(--primary-dark); }
.filter-btn.active { background: var(--primary); border-color: var(--primary); color: white; }

/* ===== Modal ===== */
.modal-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(74, 64, 54, 0.4);
  backdrop-filter: blur(4px);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  animation: fadeIn 0.2s ease;
}

.modal {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow-modal);
  width: 100%;
  max-width: 520px;
  max-height: 90vh;
  overflow-y: auto;
  animation: slideUp 0.3s ease;
}

.modal-small { max-width: 400px; }
.modal-screenshot { max-width: 600px; }

@keyframes slideUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
}

.modal-header h3 {
  font-size: 18px;
  color: var(--text-primary);
}

.modal-close {
  background: none;
  border: none;
  font-size: 24px;
  color: var(--text-light);
  cursor: pointer;
  padding: 0 4px;
  line-height: 1;
  transition: var(--transition);
}

.modal-close:hover { color: var(--danger); }

.modal-body { padding: 24px; }
.text-center { text-align: center; }

/* ===== Booking Summary ===== */
.booking-summary {
  display: flex;
  gap: 20px;
  padding: 16px;
  background: var(--bg-soft);
  border-radius: var(--radius-sm);
  margin-bottom: 24px;
}

.summary-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 15px;
  font-weight: 600;
  color: var(--primary-dark);
}

.summary-icon { font-size: 18px; }

/* ===== Form ===== */
.form-row {
  display: flex;
  gap: 16px;
}

.form-row .form-group { flex: 1; }

.form-group { margin-bottom: 18px; }

.form-group label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 6px;
}

.required { color: var(--danger); }

.form-group input[type="text"],
.form-group input[type="password"],
.form-group textarea {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--border-dark);
  border-radius: var(--radius-xs);
  font-size: 15px;
  color: var(--text-primary);
  background: var(--bg-primary);
  transition: var(--transition);
  font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(123, 160, 152, 0.15);
  background: white;
}

.form-group textarea { resize: vertical; }

.form-hint {
  display: block;
  font-size: 12px;
  color: var(--text-light);
  margin-top: 4px;
}

/* ===== Upload Area ===== */
.upload-area {
  border: 2px dashed var(--border-dark);
  border-radius: var(--radius-sm);
  transition: var(--transition);
  overflow: hidden;
}

.upload-area.has-image { border-style: solid; border-color: var(--primary); }

#upload-placeholder {
  padding: 32px 20px;
  text-align: center;
  cursor: pointer;
  transition: var(--transition);
}

#upload-placeholder:hover { background: var(--bg-soft); }

.upload-icon { display: block; font-size: 36px; margin-bottom: 8px; }
.upload-text { display: block; font-size: 15px; font-weight: 600; color: var(--text-primary); margin-bottom: 4px; }
.upload-hint { display: block; font-size: 12px; color: var(--text-light); }

#upload-preview {
  position: relative;
  padding: 12px;
  text-align: center;
}

#preview-img {
  max-width: 100%;
  max-height: 240px;
  border-radius: var(--radius-xs);
}

.remove-screenshot {
  position: absolute;
  top: 16px;
  right: 16px;
  padding: 4px 12px;
  border: none;
  background: rgba(216, 133, 115, 0.9);
  color: white;
  font-size: 13px;
  border-radius: 20px;
  cursor: pointer;
  transition: var(--transition);
}

.remove-screenshot:hover { background: var(--danger); }

/* ===== Form Actions ===== */
.form-actions {
  display: flex;
  gap: 12px;
  justify-content: flex-end;
  margin-top: 8px;
}

.btn {
  padding: 10px 24px;
  border: none;
  border-radius: var(--radius-xs);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  font-family: inherit;
}

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

.btn-primary:hover { background: var(--primary-dark); transform: translateY(-1px); box-shadow: 0 4px 12px rgba(123, 160, 152, 0.3); }

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

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

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

.btn-danger:hover { background: #C07464; }

.btn-sm {
  padding: 6px 14px;
  font-size: 13px;
}

/* ===== Confirm Text ===== */
.confirm-text {
  font-size: 15px;
  color: var(--text-primary);
  margin-bottom: 20px;
  line-height: 1.7;
}

/* ===== Screenshot Full ===== */
.screenshot-full {
  max-width: 100%;
  border-radius: var(--radius-sm);
}

/* ===== Toast ===== */
.toast {
  position: fixed;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  background: var(--text-primary);
  color: white;
  padding: 12px 28px;
  border-radius: 30px;
  font-size: 14px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.2);
  z-index: 2000;
  opacity: 0;
  transition: all 0.4s ease;
  pointer-events: none;
  white-space: nowrap;
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.toast.success { background: var(--success); }
.toast.error { background: var(--danger); }
.toast.warning { background: var(--accent); }

/* ===== Footer ===== */
.footer {
  border-top: 1px solid var(--border);
  background: var(--bg-card);
  padding: 16px 20px;
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
}

.footer p {
  font-size: 13px;
  color: var(--text-light);
}

.admin-link {
  background: none;
  border: none;
  font-size: 13px;
  color: var(--text-light);
  cursor: pointer;
  text-decoration: underline;
  transition: var(--transition);
}

.admin-link:hover { color: var(--primary); }

/* ===== Responsive ===== */
@media (max-width: 640px) {
  .header-inner { padding: 0 12px; height: 52px; }
  .logo-text { font-size: 17px; }
  .nav-btn { padding: 6px 12px; font-size: 14px; }
  .main { padding: 20px 12px 40px; }
  .page-title { font-size: 22px; }
  .page-subtitle { font-size: 14px; }
  .week-switcher { gap: 8px; }
  .week-btn { padding: 6px 12px; font-size: 13px; }
  .week-label { font-size: 15px; min-width: 60px; }
  .form-row { flex-direction: column; gap: 0; }
  .admin-stats { gap: 8px; }
  .stat-card { min-width: 90px; padding: 14px; }
  .stat-num { font-size: 24px; }
  .booking-card { padding: 16px; }
  .booking-info-grid { grid-template-columns: 1fr 1fr; gap: 8px 12px; }
  .modal { max-width: 100%; }
  .modal-body { padding: 16px; }
  .legend { gap: 12px; }
  .legend-item { font-size: 12px; }
}

/* ===== Blocked Slot (student view) ===== */
.slot.blocked {
  background: var(--danger-bg);
  color: var(--danger);
  cursor: not-allowed;
}
.slot.blocked::after { content: '不可约'; font-size: 12px; }

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

/* ===== Teacher Calendar Slots ===== */
.slot-teacher {
  min-height: 52px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-xs);
  cursor: pointer;
  transition: var(--transition);
  font-size: 13px;
  padding: 4px;
}

.slot-teacher .slot-text {
  font-weight: 600;
  font-size: 13px;
  line-height: 1.3;
}

.slot-teacher .slot-sub {
  font-size: 11px;
  opacity: 0.8;
  margin-top: 2px;
}

.slot-teacher.available {
  background: var(--primary-bg);
  color: var(--primary-dark);
}
.slot-teacher.available:hover {
  background: var(--primary-light);
  color: white;
}

.slot-teacher.blocked {
  background: var(--danger-bg);
  color: var(--danger);
}
.slot-teacher.blocked:hover {
  background: rgba(216, 133, 115, 0.2);
}

.slot-teacher.has-pending {
  background: var(--accent-bg);
  color: var(--accent);
}
.slot-teacher.has-pending:hover { background: var(--accent-light); }

.slot-teacher.has-confirmed {
  background: var(--primary-light);
  color: white;
}
.slot-teacher.has-confirmed:hover { background: var(--primary); }

.slot-teacher.past {
  background: var(--bg-tag);
  color: var(--text-light);
  cursor: not-allowed;
  opacity: 0.5;
}

/* ===== .ics Upload Card ===== */
.ics-upload-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  margin-bottom: 20px;
  border-left: 4px solid var(--primary);
}

.ics-upload-card h3 {
  font-size: 16px;
  color: var(--primary-dark);
  margin-bottom: 8px;
}

.card-desc {
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 16px;
  line-height: 1.6;
}

.ics-success {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 18px;
  background: var(--primary-bg);
  border-radius: var(--radius-sm);
  margin-top: 12px;
  font-size: 14px;
  color: var(--primary-dark);
}

.ics-icon { font-size: 20px; }

/* ===== Period Time Config ===== */
.period-config-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  margin-bottom: 20px;
  border-left: 4px solid var(--accent);
}

.config-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
}

.config-header h3 {
  font-size: 16px;
  color: var(--primary-dark);
}

.period-times-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 10px;
  margin-top: 12px;
}

.period-time-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  background: var(--bg-soft);
  border-radius: var(--radius-xs);
}

.period-time-item.edit {
  background: var(--bg-soft);
  flex-wrap: wrap;
}

.pt-label {
  font-size: 14px;
  font-weight: 600;
  color: var(--primary-dark);
  white-space: nowrap;
}

.pt-time {
  font-size: 14px;
  color: var(--text-secondary);
}

.pt-input {
  width: 70px;
  padding: 4px 6px;
  border: 1px solid var(--border-dark);
  border-radius: 6px;
  font-size: 13px;
  color: var(--text-primary);
  font-family: inherit;
}

.pt-input:focus {
  outline: none;
  border-color: var(--primary);
}

.pt-dash { color: var(--text-light); font-size: 13px; }

/* ===== Landing Page ===== */
.landing-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.landing-card {
  text-align: center;
  max-width: 500px;
  width: 100%;
}

.landing-logo {
  font-size: 48px;
  margin-bottom: 16px;
}

.landing-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--primary-dark);
  margin-bottom: 8px;
  letter-spacing: 2px;
}

.landing-subtitle {
  font-size: 16px;
  color: var(--text-secondary);
  margin-bottom: 40px;
}

.landing-buttons {
  display: flex;
  gap: 20px;
  justify-content: center;
  flex-wrap: wrap;
}

.landing-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  width: 180px;
  padding: 28px 20px;
  border-radius: var(--radius);
  text-decoration: none;
  transition: var(--transition);
  border: 2px solid transparent;
}

.landing-btn.student {
  background: var(--primary-bg);
  color: var(--primary-dark);
  border-color: var(--primary-light);
}

.landing-btn.student:hover {
  background: var(--primary);
  color: white;
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(123, 160, 152, 0.3);
}

.landing-btn.teacher {
  background: var(--accent-bg);
  color: var(--accent);
  border-color: var(--accent-light);
}

.landing-btn.teacher:hover {
  background: var(--accent);
  color: white;
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(232, 168, 124, 0.3);
}

.landing-btn-icon { font-size: 36px; }
.landing-btn-text { font-size: 18px; font-weight: 600; }
.landing-btn-desc { font-size: 13px; opacity: 0.8; }

@media (max-width: 640px) {
  .landing-buttons { flex-direction: column; align-items: center; }
  .period-times-grid { grid-template-columns: 1fr 1fr; }
}