/* ============================================
   舞蹈學校管理系統 - 主題樣式
   ============================================ */

:root {
  --primary: #3b82f6;
  --primary-dark: #2563eb;
  --primary-light: #60a5fa;
  --primary-bg: #eff6ff;
  --secondary: #1e293b;
  --accent: #f59e0b;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --info: #3b82f6;
  --gray-100: #f8f9fa;
  --gray-200: #e9ecef;
  --gray-300: #dee2e6;
  --gray-400: #ced4da;
  --gray-500: #adb5bd;
  --gray-600: #6c757d;
  --gray-700: #495057;
  --gray-800: #343a40;
  --gray-900: #212529;
  --white: #ffffff;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow: 0 2px 8px rgba(0,0,0,0.12);
  --shadow-lg: 0 4px 20px rgba(0,0,0,0.15);
  --radius: 8px;
  --radius-lg: 12px;
  --transition: all 0.2s ease;
}

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

body {
  font-family: 'Noto Sans HK', 'PingFang HK', 'Microsoft JhengHei', sans-serif;
  background: var(--gray-100);
  color: var(--gray-900);
  min-height: 100vh;
  font-size: 14px;
  line-height: 1.5;
}

/* ---- Layout ---- */
.app-wrapper { display: flex; min-height: 100vh; }

.sidebar {
  width: 220px;
  background: var(--secondary);
  color: white;
  display: flex;
  flex-direction: column;
  position: fixed;
  top: 0; left: 0; bottom: 0;
  z-index: 100;
  transition: var(--transition);
}

.sidebar-logo {
  padding: 20px 16px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
  display: flex;
  align-items: center;
  gap: 10px;
}

.sidebar-logo .logo-icon {
  width: 36px; height: 36px;
  background: var(--primary);
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 18px; font-weight: 900; color: white;
  flex-shrink: 0;
}

.sidebar-logo .logo-text { font-size: 13px; font-weight: 600; line-height: 1.3; }
.sidebar-logo .logo-sub { font-size: 11px; color: rgba(255,255,255,0.5); }

.sidebar-nav { flex: 1; padding: 12px 0; overflow-y: auto; }

.nav-section-title {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: rgba(255,255,255,0.4);
  padding: 12px 16px 4px;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 16px;
  color: rgba(255,255,255,0.75);
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition);
  border-left: 3px solid transparent;
  font-size: 13px;
}

.nav-item:hover { background: rgba(255,255,255,0.08); color: white; }
.nav-item.active { background: rgba(59,130,246,0.2); color: white; border-left-color: var(--primary); }
.nav-item .nav-icon { font-size: 16px; width: 20px; text-align: center; }

.sidebar-footer {
  padding: 12px 16px;
  border-top: 1px solid rgba(255,255,255,0.1);
}

.user-info { display: flex; align-items: center; gap: 10px; margin-bottom: 10px; }
.user-avatar {
  width: 32px; height: 32px;
  background: var(--primary);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 14px; font-weight: 700; color: white;
  flex-shrink: 0;
}
.user-name { font-size: 12px; font-weight: 600; }
.user-role { font-size: 11px; color: rgba(255,255,255,0.5); }

.btn-logout {
  width: 100%;
  padding: 7px;
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.15);
  color: rgba(255,255,255,0.7);
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 12px;
  transition: var(--transition);
}
.btn-logout:hover { background: rgba(239,68,68,0.3); color: white; }

.main-content {
  margin-left: 220px;
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.topbar {
  background: white;
  border-bottom: 1px solid var(--gray-200);
  padding: 0 24px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: sticky;
  top: 0;
  z-index: 50;
  box-shadow: var(--shadow-sm);
}

.topbar-title { font-size: 16px; font-weight: 700; color: var(--gray-900); }
.topbar-subtitle { font-size: 12px; color: var(--gray-500); margin-top: 1px; }

.page-content { padding: 24px; flex: 1; }

/* ---- Cards ---- */
.card {
  background: white;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--gray-200);
  overflow: hidden;
}

.card-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--gray-200);
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: white;
}

.card-title { font-size: 15px; font-weight: 700; color: var(--gray-900); }
.card-subtitle { font-size: 12px; color: var(--gray-500); margin-top: 2px; }
.card-body { padding: 20px; }

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  font-size: 13px;
  font-weight: 600;
  transition: var(--transition);
  text-decoration: none;
  white-space: nowrap;
  font-family: inherit;
}

.btn-primary { background: var(--primary); color: white; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-secondary { background: var(--gray-200); color: var(--gray-700); }
.btn-secondary:hover { background: var(--gray-300); }
.btn-success { background: var(--success); color: white; }
.btn-success:hover { background: #059669; }
.btn-warning { background: var(--warning); color: white; }
.btn-warning:hover { background: #d97706; }
.btn-danger { background: var(--danger); color: white; }
.btn-danger:hover { background: #dc2626; }
.btn-outline { background: transparent; border: 1px solid var(--gray-300); color: var(--gray-700); }
.btn-outline:hover { background: var(--gray-100); }
.btn-outline-primary { background: transparent; border: 1px solid var(--primary); color: var(--primary); }
.btn-outline-primary:hover { background: var(--primary-bg); }

.btn-sm { padding: 5px 10px; font-size: 12px; }
.btn-lg { padding: 11px 22px; font-size: 15px; }
.btn-icon { padding: 7px; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

/* ---- Badges ---- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  border-radius: 20px;
  font-size: 11px;
  font-weight: 600;
  white-space: nowrap;
}
.badge-primary { background: var(--primary-bg); color: var(--primary); }
.badge-success { background: #dcfce7; color: #166534; }
.badge-warning { background: #fef3c7; color: #92400e; }
.badge-danger { background: #fee2e2; color: #991b1b; }
.badge-info { background: #dbeafe; color: #1e40af; }
.badge-secondary { background: var(--gray-200); color: var(--gray-700); }

/* ---- Forms ---- */
.form-group { margin-bottom: 16px; }
.form-label { display: block; font-size: 13px; font-weight: 600; color: var(--gray-700); margin-bottom: 6px; }
.form-control {
  width: 100%;
  padding: 9px 12px;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-size: 13px;
  color: var(--gray-900);
  background: white;
  transition: var(--transition);
  outline: none;
  font-family: inherit;
}
.form-control:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(59,130,246,0.1); }
.form-control::placeholder { color: var(--gray-400); }
select.form-control { cursor: pointer; }
textarea.form-control { resize: vertical; min-height: 80px; }

.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-row-3 { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 16px; }

/* ---- Tables ---- */
.table-wrapper { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
th {
  background: var(--gray-100);
  padding: 10px 14px;
  text-align: left;
  font-size: 12px;
  font-weight: 700;
  color: var(--gray-600);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  border-bottom: 2px solid var(--gray-200);
  white-space: nowrap;
}
td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--gray-100);
  font-size: 13px;
  color: var(--gray-800);
  vertical-align: middle;
}
tr:hover td { background: var(--gray-100); }
tr:last-child td { border-bottom: none; }

/* ---- Search & Filter bar ---- */
.filter-bar {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.search-box {
  position: relative;
  flex: 1;
  min-width: 200px;
}
.search-box input {
  width: 100%;
  padding: 9px 12px 9px 36px;
  border: 1px solid var(--gray-300);
  border-radius: var(--radius);
  font-size: 13px;
  outline: none;
  transition: var(--transition);
  font-family: inherit;
}
.search-box input:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(59,130,246,0.1); }
.search-box .search-icon {
  position: absolute;
  left: 11px; top: 50%;
  transform: translateY(-50%);
  color: var(--gray-400);
  font-size: 15px;
}

/* ---- Stats row ---- */
.stats-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 16px;
  margin-bottom: 24px;
}

.stat-card {
  background: white;
  border-radius: var(--radius-lg);
  padding: 16px 20px;
  border: 1px solid var(--gray-200);
  box-shadow: var(--shadow-sm);
}
.stat-value { font-size: 28px; font-weight: 800; color: var(--primary); line-height: 1; }
.stat-label { font-size: 12px; color: var(--gray-500); margin-top: 4px; }
.stat-card.green .stat-value { color: var(--success); }
.stat-card.orange .stat-value { color: var(--accent); }
.stat-card.blue .stat-value { color: var(--info); }

/* ---- Modal ---- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
}
.modal-overlay.show { opacity: 1; visibility: visible; }

.modal {
  background: white;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 560px;
  max-height: 90vh;
  overflow-y: auto;
  transform: translateY(20px);
  transition: var(--transition);
}
.modal-overlay.show .modal { transform: translateY(0); }
.modal-lg { max-width: 800px; }
.modal-xl { max-width: 1000px; }

.modal-header {
  padding: 18px 24px;
  border-bottom: 1px solid var(--gray-200);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.modal-title { font-size: 16px; font-weight: 700; }
.modal-close {
  background: none; border: none; cursor: pointer;
  font-size: 20px; color: var(--gray-500); padding: 4px;
  border-radius: 4px; transition: var(--transition);
}
.modal-close:hover { background: var(--gray-200); color: var(--gray-900); }
.modal-body { padding: 24px; }
.modal-footer {
  padding: 16px 24px;
  border-top: 1px solid var(--gray-200);
  display: flex;
  justify-content: flex-end;
  gap: 10px;
}

/* ---- Toast ---- */
#toast-container {
  position: fixed;
  top: 20px; right: 20px;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.toast {
  background: white;
  border-radius: var(--radius);
  padding: 12px 16px;
  box-shadow: var(--shadow-lg);
  border-left: 4px solid var(--success);
  min-width: 260px;
  max-width: 360px;
  display: flex;
  align-items: center;
  gap: 10px;
  animation: slideIn 0.3s ease;
  font-size: 13px;
}
.toast.error { border-left-color: var(--danger); }
.toast.warning { border-left-color: var(--warning); }
.toast.info { border-left-color: var(--info); }
@keyframes slideIn { from { transform: translateX(100%); opacity: 0; } to { transform: translateX(0); opacity: 1; } }

/* ---- Loading ---- */
.loading-overlay {
  position: fixed; inset: 0;
  background: rgba(255,255,255,0.8);
  z-index: 9998;
  display: flex; align-items: center; justify-content: center;
  flex-direction: column; gap: 12px;
}
.spinner {
  width: 40px; height: 40px;
  border: 3px solid var(--gray-200);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ---- Empty state ---- */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--gray-500);
}
.empty-state .empty-icon { font-size: 48px; margin-bottom: 12px; opacity: 0.4; }
.empty-state h3 { font-size: 16px; font-weight: 600; margin-bottom: 6px; color: var(--gray-600); }
.empty-state p { font-size: 13px; }

/* ---- Tabs ---- */
.tabs { display: flex; border-bottom: 2px solid var(--gray-200); margin-bottom: 20px; gap: 0; }
.tab-btn {
  padding: 10px 20px;
  background: none; border: none;
  font-size: 13px; font-weight: 600;
  color: var(--gray-500); cursor: pointer;
  border-bottom: 2px solid transparent;
  margin-bottom: -2px;
  transition: var(--transition);
  font-family: inherit;
}
.tab-btn:hover { color: var(--gray-800); }
.tab-btn.active { color: var(--primary); border-bottom-color: var(--primary); }

/* ---- Checkbox ---- */
.checkbox-label {
  display: flex; align-items: center; gap: 8px;
  cursor: pointer; font-size: 13px;
}
.checkbox-label input[type=checkbox] {
  width: 16px; height: 16px; cursor: pointer;
  accent-color: var(--primary);
}

/* ---- Responsive ---- */
@media (max-width: 768px) {
  .sidebar { transform: translateX(-100%); }
  .sidebar.open { transform: translateX(0); }
  .main-content { margin-left: 0; }
  .form-row, .form-row-3 { grid-template-columns: 1fr; }
  .stats-row { grid-template-columns: 1fr 1fr; }
  .mobile-menu-btn { display: block !important; }
}

/* ---- Utilities ---- */
.text-primary { color: var(--primary); }
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-danger { color: var(--danger); }
.text-muted { color: var(--gray-500); }
.text-center { text-align: center; }
.text-right { text-align: right; }
.fw-bold { font-weight: 700; }
.d-flex { display: flex; }
.align-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-8 { gap: 8px; }
.gap-12 { gap: 12px; }
.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mb-16 { margin-bottom: 16px; }
.p-0 { padding: 0; }
.hidden { display: none !important; }
.w-full { width: 100%; }

/* ---- Login Page ---- */
.login-page {
  background: linear-gradient(135deg, #1e293b 0%, #0f172a 50%, #1e293b 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 20px;
}

.login-card {
  background: white;
  border-radius: 16px;
  padding: 40px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.3);
  width: 100%;
  max-width: 420px;
}

.login-logo {
  text-align: center;
  margin-bottom: 32px;
}

.login-logo-icon {
  width: 64px;
  height: 64px;
  background: #3b82f6;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 28px;
  font-weight: 900;
  color: white;
  margin: 0 auto 16px;
}

.login-title {
  font-size: 22px;
  font-weight: 800;
  color: #1e293b;
}

.login-subtitle {
  font-size: 13px;
  color: #6c757d;
  margin-top: 4px;
}

.login-divider {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 20px 0;
}

.login-divider-line {
  flex: 1;
  height: 1px;
  background: #e9ecef;
}

.login-divider-text {
  font-size: 12px;
  color: #adb5bd;
}

.login-demo {
  background: #f8f9fa;
  border-radius: 8px;
  padding: 12px;
  font-size: 12px;
  color: #6c757d;
}

.alert {
  background: #fee2e2;
  border: 1px solid #fca5a5;
  color: #dc2626;
  padding: 10px 14px;
  border-radius: 8px;
  font-size: 13px;
  margin-bottom: 16px;
}

.form-icon-wrapper {
  position: relative;
}

.form-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 16px;
}

.form-control.icon-input {
  padding-left: 38px;
}

/* Mobile menu button */
.mobile-menu-btn {
  display: none;
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 200;
  padding: 8px 12px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-size: 18px;
}