:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --dark: #1f2937;
  --gray: #6b7280;
  --light-gray: #f3f4f6;
  --border: #e5e7eb;
  --white: #ffffff;
  --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  color: var(--dark);
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}

/* Navigation */
.navbar {
  background: var(--white);
  box-shadow: var(--shadow);
  padding: 1rem 0;
  margin-bottom: 2rem;
}

.navbar-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.navbar-brand {
  font-size: 1.5rem;
  font-weight: bold;
  color: var(--primary);
  text-decoration: none;
}

.navbar-menu {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.navbar-link {
  color: var(--gray);
  text-decoration: none;
  padding: 0.5rem 1rem;
  border-radius: 0.5rem;
  transition: all 0.3s;
}

.navbar-link:hover {
  background: var(--light-gray);
  color: var(--primary);
}

/* Cards */
.card {
  background: var(--white);
  border-radius: 1rem;
  padding: 2rem;
  box-shadow: var(--shadow-lg);
  margin-bottom: 1.5rem;
  animation: fadeInUp 0.5s ease;
}

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

.card-header {
  margin-bottom: 1.5rem;
  border-bottom: 2px solid var(--light-gray);
  padding-bottom: 1rem;
}

.card-title {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--dark);
}

.card-subtitle {
  color: var(--gray);
  font-size: 0.9rem;
  margin-top: 0.5rem;
}

/* Buttons */
.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 0.5rem;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s;
  text-decoration: none;
  display: inline-block;
  text-align: center;
}

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

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

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

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

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

.btn-outline {
  background: transparent;
  border: 2px solid var(--primary);
  color: var(--primary);
}

.btn-block {
  width: 100%;
}

/* Forms */
.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--dark);
}

.form-control {
  width: 100%;
  padding: 0.75rem;
  border: 2px solid var(--border);
  border-radius: 0.5rem;
  font-size: 1rem;
  transition: all 0.3s;
}

.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.form-select {
  width: 100%;
  padding: 0.75rem;
  border: 2px solid var(--border);
  border-radius: 0.5rem;
  font-size: 1rem;
  background: var(--white);
  cursor: pointer;
}

/* Badge */
.badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.875rem;
  font-weight: 500;
}

.badge-success {
  background: #d1fae5;
  color: #065f46;
}

.badge-warning {
  background: #fef3c7;
  color: #92400e;
}

.badge-danger {
  background: #fee2e2;
  color: #991b1b;
}

.badge-info {
  background: #dbeafe;
  color: #1e40af;
}

/* Table */
.table-container {
  overflow-x: auto;
  border-radius: 0.5rem;
  border: 1px solid var(--border);
}

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

.table thead {
  background: var(--light-gray);
}

.table th {
  padding: 1rem;
  text-align: left;
  font-weight: 600;
  color: var(--dark);
}

.table td {
  padding: 1rem;
  border-top: 1px solid var(--border);
}

.table tbody tr:hover {
  background: var(--light-gray);
}

/* Stats Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.stat-card {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: var(--white);
  padding: 1.5rem;
  border-radius: 1rem;
  box-shadow: var(--shadow-lg);
}

.stat-value {
  font-size: 2rem;
  font-weight: bold;
  margin-bottom: 0.5rem;
}

.stat-label {
  font-size: 0.9rem;
  opacity: 0.9;
}

/* Loading Spinner */
.spinner {
  border: 3px solid var(--light-gray);
  border-top: 3px solid var(--primary);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  animation: spin 1s linear infinite;
  margin: 2rem auto;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.loading-text {
  text-align: center;
  color: var(--gray);
  margin-top: 1rem;
}

/* Toast Notification */
.toast {
  position: fixed;
  top: 20px;
  right: 20px;
  background: var(--white);
  padding: 1rem 1.5rem;
  border-radius: 0.5rem;
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  gap: 1rem;
  z-index: 1000;
  animation: slideInRight 0.3s ease;
  min-width: 300px;
}

@keyframes slideInRight {
  from {
    transform: translateX(400px);
    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-warning {
  border-left: 4px solid var(--warning);
}

/* QR Code Display */
.qr-container {
  text-align: center;
  padding: 2rem;
}

.qr-image {
  max-width: 400px;
  width: 100%;
  height: auto;
  border-radius: 1rem;
  box-shadow: var(--shadow-lg);
  margin: 2rem auto;
  display: block;
}

/* Landing Page */
.hero {
  text-align: center;
  padding: 4rem 2rem;
  color: var(--white);
}

.hero-title {
  font-size: 3rem;
  font-weight: bold;
  margin-bottom: 1rem;
}

.hero-subtitle {
  font-size: 1.25rem;
  margin-bottom: 2rem;
  opacity: 0.9;
}

/* Grid Layout */
.grid {
  display: grid;
  gap: 1.5rem;
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

/* Utility Classes */
.text-center { text-align: center; }
.text-right { text-align: right; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.p-0 { padding: 0; }
.p-1 { padding: 0.5rem; }
.p-2 { padding: 1rem; }
.hidden { display: none; }
.flex { display: flex; }
.flex-between { justify-content: space-between; }
.flex-center { justify-content: center; }
.items-center { align-items: center; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }

/* Responsive */
@media (max-width: 768px) {
  .hero-title {
    font-size: 2rem;
  }
  
  .stats-grid {
    grid-template-columns: 1fr;
  }
  
  .navbar-content {
    flex-direction: column;
    gap: 1rem;
  }
  
  .toast {
    left: 20px;
    right: 20px;
    min-width: auto;
  }
}