/* =====================================================
   ValU AI — Component Styles
   Navigation, Buttons, Cards, Forms, Tables
   ===================================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=Noto+Serif+SC:wght@400;600;700&family=JetBrains+Mono:wght@400;500;600;700&display=swap');

/* --- Navigation Bar --- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: rgba(12, 17, 28, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-subtle);
  z-index: 1000;
  transition: background var(--transition-base);
}

.navbar.scrolled {
  background: rgba(12, 17, 28, 0.98);
  border-bottom-color: var(--border-card);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.navbar-brand:hover {
  color: var(--accent-primary);
}

.navbar-brand svg {
  width: 32px;
  height: 32px;
  fill: var(--accent-primary);
}

.navbar-menu {
  display: flex;
  align-items: center;
  gap: var(--spacing-xl);
  list-style: none;
}

.navbar-menu a {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.95rem;
  transition: color var(--transition-fast);
  position: relative;
}

.navbar-menu a:hover,
.navbar-menu a.active {
  color: var(--text-primary);
}

.navbar-menu a.active::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--accent-primary);
  border-radius: 1px;
}

.navbar-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: var(--spacing-xs);
  background: none;
  border: none;
}

.hamburger span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: all var(--transition-base);
}

.hamburger.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
}

.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xs);
  padding: 0.625rem 1.25rem;
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  white-space: nowrap;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-primary-hover));
  color: white;
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.25);
}

.btn-primary:hover:not(:disabled) {
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.35);
  transform: translateY(-1px);
}

.btn-secondary {
  background: transparent;
  color: var(--accent-primary);
  border: 1.5px solid var(--accent-primary);
}

.btn-secondary:hover:not(:disabled) {
  background: rgba(59, 130, 246, 0.1);
  transform: translateY(-1px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1.5px solid var(--border-card);
}

.btn-ghost:hover:not(:disabled) {
  color: var(--text-primary);
  border-color: var(--text-secondary);
  background: rgba(255, 255, 255, 0.03);
}

.btn-sm {
  padding: 0.375rem 0.875rem;
  font-size: 0.85rem;
  border-radius: 6px;
}

.btn-lg {
  padding: 0.875rem 2rem;
  font-size: 1.05rem;
  border-radius: 10px;
}

.btn-wechat {
  background: #07c160;
  color: white;
}

.btn-wechat:hover:not(:disabled) {
  background: #06ad56;
  transform: translateY(-1px);
}

/* --- Cards --- */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-card);
  border-radius: 12px;
  padding: var(--spacing-xl);
  transition: all var(--transition-base);
}

.card:hover {
  border-color: rgba(59, 130, 246, 0.3);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
}

.card-accent-blue { border-top: 3px solid var(--accent-primary); }
.card-accent-green { border-top: 3px solid var(--accent-success); }
.card-accent-purple { border-top: 3px solid #8b5cf6; }
.card-accent-amber { border-top: 3px solid var(--accent-warning); }
.card-accent-red { border-top: 3px solid var(--accent-danger); }

/* --- Grid Layouts --- */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-xl);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-xl);
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--spacing-xl);
}

/* --- Forms --- */
.form-group {
  margin-bottom: var(--spacing-lg);
}

.form-label {
  display: block;
  margin-bottom: var(--spacing-xs);
  font-weight: 500;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.form-input {
  width: 100%;
  padding: 0.75rem 1rem;
  background: var(--bg-input);
  border: 1.5px solid var(--border-card);
  border-radius: 8px;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 1rem;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus {
  outline: none;
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px var(--border-focus);
}

.form-input::placeholder {
  color: var(--text-muted);
}

.form-hint {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: var(--spacing-xs);
}

.form-error {
  font-size: 0.8rem;
  color: var(--accent-danger);
  margin-top: var(--spacing-xs);
}

/* --- Badge / Tag --- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.625rem;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 999px;
  white-space: nowrap;
}

.badge-blue {
  background: rgba(59, 130, 246, 0.15);
  color: var(--accent-primary);
}

.badge-green {
  background: rgba(16, 185, 129, 0.15);
  color: var(--accent-success);
}

.badge-amber {
  background: rgba(245, 158, 11, 0.15);
  color: var(--accent-warning);
}

.badge-red {
  background: rgba(239, 68, 68, 0.15);
  color: var(--accent-danger);
}

/* --- Tables --- */
.table-container {
  overflow-x: auto;
  border: 1px solid var(--border-card);
  border-radius: 12px;
  background: var(--bg-card);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.data-table thead {
  background: var(--bg-secondary);
}

.data-table th {
  padding: var(--spacing-md) var(--spacing-lg);
  text-align: left;
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-bottom: 1px solid var(--border-card);
}

.data-table td {
  padding: var(--spacing-md) var(--spacing-lg);
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-primary);
}

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

.data-table tbody tr:hover {
  background: rgba(59, 130, 246, 0.03);
}

.data-table .mono {
  font-family: var(--font-mono);
  font-weight: 500;
}

/* --- Progress Bar --- */
.progress-bar {
  width: 100%;
  height: 8px;
  background: var(--bg-elevated);
  border-radius: 4px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent-primary), #60a5fa);
  border-radius: 4px;
  transition: width var(--transition-slow);
}

/* --- Steps / Timeline --- */
.steps {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0;
  margin: var(--spacing-2xl) 0;
}

.step {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-sm);
  flex: 0 0 auto;
}

.step-number {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-elevated);
  border: 2px solid var(--border-card);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--text-muted);
  transition: all var(--transition-base);
}

.step.active .step-number {
  background: var(--accent-primary);
  border-color: var(--accent-primary);
  color: white;
}

.step.completed .step-number {
  background: var(--accent-success);
  border-color: var(--accent-success);
  color: white;
}

.step-label {
  font-size: 0.8rem;
  color: var(--text-muted);
  text-align: center;
  max-width: 80px;
}

.step.active .step-label {
  color: var(--text-primary);
}

.step-line {
  width: 60px;
  height: 2px;
  background: var(--border-card);
  margin: 0 var(--spacing-xs);
  align-self: center;
  margin-bottom: 28px;
}

.step-line.completed {
  background: var(--accent-success);
}

/* --- Footer --- */
.footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-subtle);
  padding: var(--spacing-2xl) 0;
  margin-top: var(--spacing-3xl);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: var(--spacing-2xl);
}

.footer-brand p {
  font-size: 0.9rem;
  margin-top: var(--spacing-md);
}

.footer-links h4 {
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-md);
}

.footer-links ul {
  list-style: none;
}

.footer-links li {
  margin-bottom: var(--spacing-xs);
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.9rem;
  transition: color var(--transition-fast);
}

.footer-links a:hover {
  color: var(--text-primary);
}

.footer-bottom {
  margin-top: var(--spacing-2xl);
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--border-subtle);
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .navbar-menu {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: rgba(12, 17, 28, 0.98);
    flex-direction: column;
    padding: var(--spacing-lg);
    gap: var(--spacing-md);
    border-bottom: 1px solid var(--border-card);
  }
  
  .navbar-menu.open {
    display: flex;
  }
  
  .navbar-actions {
    display: none;
  }
  
  .hamburger {
    display: flex;
  }
  
  .steps {
    flex-wrap: wrap;
    gap: var(--spacing-md);
  }
  
  .step-line {
    display: none;
  }
  
  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
  }
}