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

:root {
  --primary-color: #4F46E5;
  --primary-dark: #4338CA;
  --primary-light: #6366F1;
  --secondary-color: #10B981;
  --danger-color: #EF4444;
  --warning-color: #F59E0B;
  --success-color: #10B981;
  --text-primary: #1F2937;
  --text-secondary: #6B7280;
  --text-light: #9CA3AF;
  --bg-primary: #FFFFFF;
  --bg-secondary: #F9FAFB;
  --bg-tertiary: #F3F4F6;
  --border-color: #E5E7EB;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans', sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  padding: 20px;
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container {
  max-width: 500px;
  margin: 0 auto;
  padding: 20px;
}

.admin-container {
  max-width: 1200px;
  margin: 0 auto;
}

.card {
  background: var(--bg-primary);
  border-radius: var(--radius-xl);
  padding: 32px;
  box-shadow: var(--shadow-xl);
  margin-bottom: 24px;
  border: 1px solid var(--border-color);
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.card:hover {
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.15);
  transform: translateY(-2px);
}

h1 {
  color: var(--text-primary);
  margin-bottom: 24px;
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
}

h2 {
  color: var(--text-primary);
  margin-bottom: 20px;
  font-size: 24px;
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.3;
}

h3 {
  color: var(--text-primary);
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 16px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  color: #555;
  font-weight: 500;
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 12px 16px;
  border: 2px solid var(--border-color);
  border-radius: var(--radius-md);
  font-size: 15px;
  font-family: inherit;
  transition: all 0.2s ease;
  background: var(--bg-primary);
  color: var(--text-primary);
}

.form-group input:hover,
.form-group textarea:hover,
.form-group select:hover {
  border-color: var(--primary-light);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--text-light);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border: none;
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  text-decoration: none;
  text-align: center;
  position: relative;
  overflow: hidden;
  letter-spacing: 0.01em;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(255,255,255,0.2) 0%, rgba(255,255,255,0) 100%);
  opacity: 0;
  transition: opacity 0.2s;
}

.btn:hover::before {
  opacity: 1;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
  color: white;
  width: 100%;
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 24px -10px rgba(79, 70, 229, 0.5);
}

.btn-primary:active {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--bg-secondary);
  color: var(--text-primary);
  width: 100%;
  border: 2px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background: var(--bg-tertiary);
  border-color: var(--text-light);
  transform: translateY(-1px);
}

.btn-success {
  background: linear-gradient(135deg, var(--success-color) 0%, #059669 100%);
  color: white;
  box-shadow: var(--shadow-md);
}

.btn-success:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 24px -10px rgba(16, 185, 129, 0.5);
}

.btn-danger {
  background: linear-gradient(135deg, var(--danger-color) 0%, #DC2626 100%);
  color: white;
  box-shadow: var(--shadow-md);
}

.btn-danger:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 24px -10px rgba(239, 68, 68, 0.5);
}

.btn-small {
  padding: 8px 16px;
  font-size: 14px;
  font-weight: 500;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none !important;
}

.button-group {
  display: flex;
  flex-direction: column;
  gap: 15px;
  margin-top: 20px;
}

.link-group {
  text-align: center;
  margin-top: 20px;
}

.link-group a {
  color: #667eea;
  text-decoration: none;
}

.message, .error {
  padding: 16px 20px;
  border-radius: var(--radius-md);
  margin-top: 16px;
  text-align: center;
  font-weight: 500;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  animation: slideDown 0.3s ease;
}

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

.message {
  background: linear-gradient(135deg, #D1FAE5 0%, #A7F3D0 100%);
  color: #065F46;
  border: 2px solid #6EE7B7;
}

.message::before {
  content: '✓';
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  background: #10B981;
  color: white;
  border-radius: 50%;
  font-weight: bold;
}

.error {
  background: linear-gradient(135deg, #FEE2E2 0%, #FECACA 100%);
  color: #991B1B;
  border: 2px solid #FCA5A5;
}

.error::before {
  content: '✕';
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  background: #EF4444;
  color: white;
  border-radius: 50%;
  font-weight: bold;
}

.loading {
  text-align: center;
  padding: 48px;
  color: white;
  font-size: 18px;
  font-weight: 500;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

.loading::before {
  content: '';
  width: 48px;
  height: 48px;
  border: 4px solid rgba(255, 255, 255, 0.3);
  border-top-color: white;
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

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

.info-item {
  padding: 12px 0;
  border-bottom: 1px solid #f0f0f0;
}

.info-item:last-child {
  border-bottom: none;
}

.info-item strong {
  color: #667eea;
  margin-right: 10px;
}

.admin-header {
  background: var(--bg-primary);
  padding: 24px 32px;
  border-radius: var(--radius-xl);
  margin-bottom: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-color);
  position: relative;
}

.admin-header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color) 0%, var(--primary-light) 100%);
  border-radius: var(--radius-xl) var(--radius-xl) 0 0;
}

.user-info {
  display: flex;
  align-items: center;
  gap: 15px;
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

.qrcode-list {
  display: grid;
  gap: 20px;
}

.qrcode-item {
  border: 2px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  background: var(--bg-primary);
  position: relative;
  overflow: hidden;
}

.qrcode-item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: linear-gradient(180deg, var(--primary-color) 0%, var(--primary-light) 100%);
  opacity: 0;
  transition: opacity 0.3s;
}

.qrcode-item:hover {
  border-color: var(--primary-light);
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.qrcode-item:hover::before {
  opacity: 1;
}

.qrcode-info h3 {
  margin-bottom: 12px;
  color: var(--text-primary);
  font-size: 18px;
  font-weight: 600;
}

.qrcode-info p {
  color: var(--text-secondary);
  margin: 8px 0;
  font-size: 14px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.qrcode-info p strong {
  color: var(--text-primary);
  font-weight: 600;
}

.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.01em;
  transition: all 0.2s;
}

.status-badge::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  animation: pulse 2s infinite;
}

.status-bound {
  background: linear-gradient(135deg, #D1FAE5 0%, #A7F3D0 100%);
  color: #065F46;
  border: 1px solid #6EE7B7;
}

.status-bound::before {
  background: #10B981;
}

.status-unbound {
  background: linear-gradient(135deg, #FEF3C7 0%, #FDE68A 100%);
  color: #92400E;
  border: 1px solid #FCD34D;
}

.status-unbound::before {
  background: #F59E0B;
}

.status-active {
  background: linear-gradient(135deg, #DBEAFE 0%, #BFDBFE 100%);
  color: #1E40AF;
  border: 1px solid #93C5FD;
}

.status-active::before {
  background: #3B82F6;
}

.status-inactive {
  background: linear-gradient(135deg, #FEE2E2 0%, #FECACA 100%);
  color: #991B1B;
  border: 1px solid #FCA5A5;
}

.status-inactive::before {
  background: #EF4444;
}

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

.modal {
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  animation: fadeIn 0.2s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

.modal-content {
  background: var(--bg-primary);
  padding: 32px;
  border-radius: var(--radius-xl);
  max-width: 600px;
  width: 90%;
  max-height: 85vh;
  overflow-y: auto;
  position: relative;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  animation: slideUp 0.3s ease;
  border: 1px solid var(--border-color);
}

@keyframes slideUp {
  from {
    transform: translateY(20px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.modal-content::-webkit-scrollbar {
  width: 8px;
}

.modal-content::-webkit-scrollbar-track {
  background: var(--bg-secondary);
  border-radius: 4px;
}

.modal-content::-webkit-scrollbar-thumb {
  background: var(--text-light);
  border-radius: 4px;
}

.modal-content::-webkit-scrollbar-thumb:hover {
  background: var(--text-secondary);
}

.close {
  position: absolute;
  right: 24px;
  top: 24px;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  font-weight: 300;
  color: var(--text-light);
  cursor: pointer;
  border-radius: 50%;
  transition: all 0.2s;
  background: var(--bg-secondary);
}

.close:hover {
  color: var(--text-primary);
  background: var(--bg-tertiary);
  transform: rotate(90deg);
}

.scan-log-item {
  padding: 15px;
  border: 1px solid #e0e0e0;
  border-radius: 8px;
  margin-bottom: 10px;
}

@media (max-width: 768px) {
  .admin-header {
    flex-direction: column;
    gap: 15px;
  }
  
  .card-header {
    flex-direction: column;
    gap: 15px;
  }
}

.admin-nav {
  background: var(--bg-primary);
  padding: 0 32px;
  border-radius: var(--radius-xl);
  margin-bottom: 24px;
  display: flex;
  gap: 8px;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
  overflow-x: auto;
}

.admin-nav::-webkit-scrollbar {
  height: 4px;
}

.admin-nav::-webkit-scrollbar-track {
  background: transparent;
}

.admin-nav::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: 2px;
}

.nav-btn {
  padding: 16px 24px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  border-bottom: 3px solid transparent;
  transition: all 0.2s ease;
  white-space: nowrap;
  position: relative;
}

.nav-btn::before {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%) scaleX(0);
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--primary-color) 0%, var(--primary-light) 100%);
  transition: transform 0.2s ease;
}

.nav-btn:hover {
  color: var(--primary-color);
  background: var(--bg-secondary);
}

.nav-btn.active {
  color: var(--primary-color);
}

.nav-btn.active::before {
  transform: translateX(-50%) scaleX(1);
}

.tab-section {
  animation: fadeIn 0.3s;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.users-list {
  display: grid;
  gap: 15px;
}

.user-item {
  border: 2px solid #e0e0e0;
  border-radius: 8px;
  padding: 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: all 0.3s;
}

.user-item:hover {
  border-color: #667eea;
  box-shadow: 0 5px 15px rgba(0,0,0,0.1);
}

.user-item-info h3 {
  margin-bottom: 10px;
  color: #333;
}

.user-item-info p {
  color: #666;
  margin: 5px 0;
  font-size: 14px;
}

.user-item-actions {
  display: flex;
  gap: 10px;
  flex-direction: column;
}

.status-active {
  background: #d4edda;
  color: #155724;
}

.status-inactive {
  background: #f8d7da;
  color: #721c24;
}

.user-stats {
  display: flex;
  gap: 20px;
  margin-top: 10px;
}

.user-stat {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 13px;
  color: #999;
}