:root {
  --primary-color: #6366f1;
  --primary-hover: #4f46e5;
  --secondary-color: #8b5cf6;
  --accent-color: #06b6d4;
  --success-color: #10b981;
  --danger-color: #ef4444;
  --warning-color: #f59e0b;
  --info-color: #3b82f6;
  --bg-dark: #0f172a;
  --bg-card: #1e293b;
  --bg-card-hover: #334155;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --border-color: #334155;
  --shadow-glow: 0 0 20px rgba(99, 102, 241, 0.3);
}

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

body {
  font-family: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
  min-height: 100vh;
  color: var(--text-primary);
}

/* Navbar */
.navbar {
  background: rgba(18, 24, 38, 0.95) !important;
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
  box-shadow: 0 4px 20px rgba(99, 102, 241, 0.15);
}

.navbar-brand {
  color: var(--text-primary) !important;
  font-weight: 700;
  letter-spacing: 1px;
}

.nav-link {
  color: var(--text-secondary) !important;
  font-weight: 500;
  transition: all 0.3s ease;
  position: relative;
}

.nav-link:hover,
.nav-link.active {
  color: var(--text-primary) !important;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background: var(--primary-color);
  transition: all 0.3s ease;
  transform: translateX(-50%);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 80%;
}

/* Cards */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
  transition: all 0.3s ease;
}

.card:hover {
  box-shadow: 0 12px 40px rgba(99, 102, 241, 0.2);
  border-color: var(--primary-color);
}

/* Card Header */
.card-header {
  background: linear-gradient(135deg, var(--bg-card) 0%, rgba(99, 102, 241, 0.1) 100%);
  border-bottom: 1px solid var(--border-color);
  border-radius: 16px 16px 0 0;
  font-weight: 600;
  color: var(--text-primary) !important;
}

.card-title {
  color: var(--text-primary) !important;
}

.card-body {
  padding: 1.5rem;
}

.card-body h5,
.card-body h6,
.card-body .card-title {
  color: var(--text-primary) !important;
}

.card-body p,
.card-body span,
.card-body div {
  color: var(--text-primary);
}

.card-body .text-muted {
  color: var(--text-secondary) !important;
}

/* Buttons */
.btn {
  font-weight: 600;
  padding: 0.625rem 1.5rem;
  border-radius: 10px;
  border: none;
  transition: all 0.3s ease;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  font-size: 0.875rem;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
  box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(99, 102, 241, 0.6);
}

.btn-success {
  background: linear-gradient(135deg, var(--success-color) 0%, #059669 100%);
  box-shadow: 0 4px 15px rgba(16, 185, 129, 0.4);
}

.btn-danger {
  background: linear-gradient(135deg, var(--danger-color) 0%, #dc2626 100%);
  box-shadow: 0 4px 15px rgba(239, 68, 68, 0.4);
}

.btn-warning {
  background: linear-gradient(135deg, var(--warning-color) 0%, #d97706 100%);
  box-shadow: 0 4px 15px rgba(245, 158, 11, 0.4);
}

.btn-info {
  background: linear-gradient(135deg, var(--info-color) 0%, #2563eb 100%);
  box-shadow: 0 4px 15px rgba(59, 130, 246, 0.4);
}

.btn-secondary {
  background: var(--bg-card-hover);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}

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

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

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

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

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

/* Forms */
.form-control,
.form-select {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  color: var(--text-primary);
  padding: 0.75rem 1rem;
  transition: all 0.3s ease;
}

.form-control:focus,
.form-select:focus {
  background: var(--bg-card-hover);
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
  color: var(--text-primary);
}

.form-control::placeholder {
  color: var(--text-secondary);
}

.form-label {
  color: var(--text-primary);
  font-weight: 500;
  margin-bottom: 0.5rem;
}

/* Table */
.table {
  color: var(--text-primary);
  background: var(--bg-card);
  border-radius: 10px;
  overflow: hidden;
}

.table thead th {
  background: var(--bg-card-hover);
  border-bottom: 2px solid var(--primary-color);
  color: var(--text-primary);
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.75rem;
  letter-spacing: 1px;
  padding: 1rem;
}

.table tbody tr {
  transition: all 0.3s ease;
  border-bottom: 1px solid var(--border-color);
}

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

.table tbody tr:hover {
  background: var(--bg-card-hover);
  transform: scale(1.01);
}

.table td,
.table th {
  border-color: var(--border-color);
  vertical-align: middle;
  padding: 1rem;
  color: var(--text-primary);
}

.table td {
  background: transparent;
}

/* Badge */
.badge {
  padding: 0.35rem 0.75rem;
  font-weight: 600;
  border-radius: 8px;
  font-size: 0.75rem;
  letter-spacing: 0.5px;
}

.badge.bg-secondary {
  background: var(--bg-card-hover) !important;
  color: var(--text-primary) !important;
  border: 1px solid var(--border-color);
}

.badge.bg-success {
  background: var(--success-color) !important;
  color: white !important;
  box-shadow: 0 2px 8px rgba(16, 185, 129, 0.3);
}

.badge.bg-danger {
  background: var(--danger-color) !important;
  color: white !important;
  box-shadow: 0 2px 8px rgba(239, 68, 68, 0.3);
}

.badge.bg-primary {
  background: var(--primary-color) !important;
  color: white !important;
  box-shadow: 0 2px 8px rgba(99, 102, 241, 0.3);
}

.badge.bg-info {
  background: var(--info-color) !important;
  color: white !important;
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.3);
}

.badge.bg-warning {
  background: var(--warning-color) !important;
  color: white !important;
  box-shadow: 0 2px 8px rgba(245, 158, 11, 0.3);
}

/* Modal */
.modal-content {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
}

.modal-header {
  background: var(--bg-card-hover);
  border-bottom: 1px solid var(--border-color);
  border-radius: 16px 16px 0 0;
}

.modal-title {
  color: var(--text-primary) !important;
}

.modal-body {
  color: var(--text-primary);
}

.modal-body p,
.modal-body span,
.modal-body div {
  color: var(--text-primary);
}

.modal-footer {
  border-top: 1px solid var(--border-color);
  border-radius: 0 0 16px 16px;
}

.btn-close {
  filter: invert(1);
}

/* Accordion */
.accordion-button {
  background: var(--bg-card);
  color: var(--text-primary);
  border: none;
  font-weight: 500;
}

.accordion-button:not(.collapsed) {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.1) 0%, rgba(99, 102, 241, 0.05) 100%);
  color: var(--text-primary);
  box-shadow: 0 2px 8px rgba(99, 102, 241, 0.15);
}

.accordion-button:focus {
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.accordion-body {
  background: var(--bg-card);
  color: var(--text-primary);
}

.accordion-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  overflow: hidden;
}

/* Toast */
.toast {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
  border-radius: 12px;
}

.toast-body {
  color: var(--text-primary);
}

/* Pagination */
.page-link {
  background: var(--bg-card);
  border-color: var(--border-color);
  color: var(--text-primary);
}

.page-link:hover {
  background: var(--bg-card-hover);
  border-color: var(--primary-color);
  color: var(--text-primary);
}

.page-item.active .page-link {
  background: var(--primary-color);
  border-color: var(--primary-color);
  color: white;
}

/* Alert */
.alert {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  border-radius: 12px;
}

.alert-warning {
  background: rgba(245, 158, 11, 0.1);
  border-color: var(--warning-color);
  color: var(--text-primary);
}

.alert-success {
  background: rgba(16, 185, 129, 0.1);
  border-color: var(--success-color);
  color: var(--text-primary);
}

.alert-danger {
  background: rgba(239, 68, 68, 0.1);
  border-color: var(--danger-color);
  color: var(--text-primary);
}

.alert-info {
  background: rgba(59, 130, 246, 0.1);
  border-color: var(--info-color);
  color: var(--text-primary);
}

/* Stat Cards */
.stat-card {
  background: linear-gradient(135deg, var(--bg-card) 0%, var(--bg-card-hover) 100%);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 1.5rem;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.stat-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
}

.stat-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-glow);
}

.stat-icon {
  font-size: 2.5rem;
  margin-bottom: 0.5rem;
  opacity: 0.9;
}

.stat-value {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.stat-label {
  font-size: 0.875rem;
  font-weight: 500;
  opacity: 0.8;
}

/* Toast notifications */
.alert.position-fixed {
  animation: slideInRight 0.3s ease;
}

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

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

.spinner-border {
  animation: spin 1s linear infinite;
}

@keyframes spin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

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

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

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

::-webkit-scrollbar-thumb:hover {
  background: var(--primary-color);
}

/* Responsive */
@media (max-width: 768px) {
  .navbar-collapse {
    background: var(--bg-card);
    border-radius: 0 0 16px 16px;
    padding: 1rem;
    margin-top: 0.5rem;
    border: 1px solid var(--border-color);
  }
  
  .stat-card {
    margin-bottom: 1rem;
  }
  
  .card {
    margin-bottom: 1rem;
  }
}

/* Animations */
.fade-in {
  animation: fadeIn 0.5s ease;
}

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

.glow-effect {
  animation: glow 2s ease-in-out infinite alternate;
}

@keyframes glow {
  from {
    box-shadow: 0 0 10px rgba(99, 102, 241, 0.5);
  }
  to {
    box-shadow: 0 0 20px rgba(99, 102, 241, 0.8), 0 0 30px rgba(139, 92, 246, 0.6);
  }
}

/* Utility classes */
.text-gradient {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color), var(--accent-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.border-gradient {
  border: 2px solid;
  border-image: linear-gradient(135deg, var(--primary-color), var(--secondary-color)) 1;
}

.bg-gradient {
  background: linear-gradient(135deg, var(--bg-card) 0%, var(--bg-card-hover) 100%);
}

/* File Upload Area */
.file-upload-area {
  border: 3px dashed var(--border-color);
  border-radius: 16px;
  padding: 3rem 2rem;
  text-align: center;
  transition: all 0.3s ease;
  background: var(--bg-card);
  position: relative;
  overflow: hidden;
}

.file-upload-area::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.05) 0%, rgba(139, 92, 246, 0.05) 100%);
  opacity: 0;
  transition: opacity 0.3s ease;
  pointer-events: none;
}

.file-upload-area:hover::before {
  opacity: 1;
}

.file-upload-area:hover {
  border-color: var(--primary-color);
  background: var(--bg-card-hover);
  box-shadow: 0 8px 30px rgba(99, 102, 241, 0.2);
  transform: translateY(-2px);
}

.file-upload-area.drag-over {
  border-color: var(--success-color);
  background: rgba(16, 185, 129, 0.1);
  box-shadow: 0 8px 30px rgba(16, 185, 129, 0.3);
  transform: scale(1.02);
}

.file-upload-area.drag-over .upload-icon {
  color: var(--success-color);
  transform: scale(1.2);
}

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

.upload-icon {
  font-size: 4rem;
  color: var(--primary-color);
  margin-bottom: 1.5rem;
  transition: all 0.3s ease;
  display: inline-block;
}

.upload-title {
  color: var(--text-primary);
  font-weight: 600;
  margin-bottom: 0.5rem;
  font-size: 1.25rem;
}

.upload-subtitle {
  color: var(--text-secondary);
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

.upload-btn {
  padding: 0.875rem 2rem;
  font-size: 1rem;
  border-radius: 12px;
  font-weight: 600;
  transition: all 0.3s ease;
}

.upload-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
}

.upload-hint {
  color: var(--text-secondary);
  margin-top: 1.5rem;
  font-size: 0.875rem;
  line-height: 1.6;
}

.upload-hint i {
  color: var(--info-color);
  margin-right: 0.25rem;
}

.selected-file {
  margin-top: 1rem;
  padding: 0.75rem 1rem;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid var(--success-color);
  border-radius: 8px;
  color: var(--success-color);
  font-weight: 500;
  display: none;
}

.selected-file.show {
  display: block;
  animation: fadeIn 0.3s ease;
}

.selected-file i {
  margin-right: 0.5rem;
}