/* 全局样式 - Mnova E-commerce Design System */
:root {
  /* Design System Colors */
  --primary: #059669;
  --primary-dark: #047857;
  --secondary: #10B981;
  --cta: #F97316;
  --cta-hover: #EA580C;
  --bg: #ECFDF5;
  --bg-alt: #D1FAE5;
  --text: #064E3B;
  --text-light: #374151;
  --text-muted: #6B7280;
  --white: #ffffff;
  --border: #D1FAE5;
  --maxw: 1200px;
  --font-heading: 'Rubik', sans-serif;
  --font-body: 'Nunito Sans', sans-serif;
  --transition: 0.3s ease;
  --shadow-sm: 0 1px 3px rgba(6, 150, 105, 0.1);
  --shadow-md: 0 4px 12px rgba(6, 150, 105, 0.15);
  --shadow-lg: 0 8px 24px rgba(6, 150, 105, 0.2);
}

* {
  box-sizing: border-box;
}

body {
  font-family: var(--font-body);
  margin: 0;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  font-size: 16px;
}

.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.site-header {
  background: var(--white);
  border-bottom: 1px solid var(--border);
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  box-shadow: var(--shadow-sm);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  font-size: 1.5rem;
  font-family: var(--font-heading);
}

.logo-icon {
  width: 32px;
  height: 32px;
}

.nav-toggle {
  display: none;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--text);
}

.nav-toggle svg {
  width: 24px;
  height: 24px;
}

.main-nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 8px;
}

.main-nav a {
  text-decoration: none;
  color: var(--text-light);
  padding: 10px 18px;
  border-radius: 8px;
  font-weight: 600;
  transition: all var(--transition);
  font-size: 0.95rem;
  display: block;
}

.main-nav a:hover,
.main-nav a.active {
  background: var(--bg);
  color: var(--primary);
}

/* Main content */
main {
  margin-top: 72px;
  min-height: calc(100vh - 144px);
}

/* Hero Section */
.hero {
  padding: 100px 0 80px;
  background: var(--white);
  position: relative;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  top: 0;
  right: 0;
  width: 50%;
  height: 100%;
  background: linear-gradient(135deg, var(--bg-alt) 0%, var(--bg) 100%);
  border-radius: 0 0 0 100%;
  opacity: 0.6;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 680px;
}

.hero-badge {
  display: inline-block;
  background: var(--bg-alt);
  color: var(--primary);
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 20px;
}

.hero h1 {
  font-family: var(--font-heading);
  margin: 0 0 20px;
  font-size: 3.5rem;
  font-weight: 700;
  color: var(--text);
  line-height: 1.15;
}

.hero-sub {
  margin: 0 0 32px;
  color: var(--text-muted);
  font-size: 1.25rem;
  line-height: 1.6;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 48px;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  border-radius: 10px;
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  transition: all var(--transition);
  border: none;
  cursor: pointer;
  font-family: var(--font-body);
}

.btn svg {
  width: 20px;
  height: 20px;
}

.btn-primary {
  background: var(--cta);
  color: var(--white);
  box-shadow: 0 4px 12px rgba(249, 115, 22, 0.3);
}

.btn-primary:hover {
  background: var(--cta-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(249, 115, 22, 0.4);
  color: var(--white);
}

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

.btn-secondary:hover {
  background: var(--border);
  transform: translateY(-2px);
  color: var(--primary-dark);
}

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

.btn-white:hover {
  background: var(--bg-alt);
  transform: translateY(-2px);
  color: var(--primary-dark);
}

/* Hero Stats */
.hero-stats {
  display: flex;
  gap: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
}

.stat {
  display: flex;
  flex-direction: column;
}

.stat-value {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 700;
  color: var(--primary);
}

.stat-label {
  font-size: 0.95rem;
  color: var(--text-muted);
}

/* Features Section */
.features {
  padding: 100px 0;
  background: var(--white);
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-header h2 {
  font-family: var(--font-heading);
  margin: 0 0 12px;
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--text);
}

.section-header p {
  margin: 0;
  color: var(--text-muted);
  font-size: 1.15rem;
}

.features .grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
}

.card {
  background: var(--white);
  padding: 32px;
  border-radius: 16px;
  box-shadow: var(--shadow-md);
  border: 2px solid var(--border);
  transition: all var(--transition);
  text-decoration: none;
  display: block;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
  color: inherit;
}

.feature-card {
  color: var(--text);
}

.card-icon {
  width: 56px;
  height: 56px;
  background: var(--bg);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  transition: all var(--transition);
}

.card:hover .card-icon {
  background: var(--primary);
  color: var(--white);
}

.card-icon svg {
  width: 28px;
  height: 28px;
}

.card h3 {
  font-family: var(--font-heading);
  margin: 0 0 12px;
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--text);
}

.card p {
  margin: 0 0 16px;
  color: var(--text-muted);
  line-height: 1.6;
  font-size: 1rem;
}

.card-link {
  color: var(--primary);
  font-weight: 600;
  font-size: 0.95rem;
}

/* CTA Section */
.cta {
  padding: 100px 0;
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  text-align: center;
}

.cta h2 {
  font-family: var(--font-heading);
  margin: 0 0 16px;
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--white);
}

.cta p {
  margin: 0 0 32px;
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.15rem;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--white);
  padding: 40px 0;
}

.site-footer p {
  margin: 0;
  color: var(--text-muted);
  text-align: center;
  font-size: 0.9rem;
}

/* Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.card {
  animation: fadeInUp 0.6s ease-out backwards;
}

.card:nth-child(1) { animation-delay: 0s; }
.card:nth-child(2) { animation-delay: 0.1s; }
.card:nth-child(3) { animation-delay: 0.2s; }
.card:nth-child(4) { animation-delay: 0.3s; }

/* Responsive */
@media (max-width: 1024px) {
  .hero h1 {
    font-size: 2.75rem;
  }
  
  .hero-stats {
    gap: 32px;
  }
  
  .stat-value {
    font-size: 1.75rem;
  }
}

@media (max-width: 768px) {
  .header-inner {
    height: 64px;
    padding: 0 16px;
  }
  
  .main-nav {
    display: none;
  }
  
  .nav-toggle {
    display: block;
  }
  
  .main-nav.open {
    display: block;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--white);
    padding: 16px;
    box-shadow: var(--shadow-md);
  }
  
  .main-nav.open ul {
    flex-direction: column;
    gap: 8px;
  }
  
  .main-nav.open a {
    padding: 12px 16px;
  }
  
  main {
    margin-top: 64px;
  }
  
  .hero {
    padding: 60px 0 50px;
  }
  
  .hero-bg {
    width: 100%;
    height: 40%;
    top: auto;
    bottom: 0;
    border-radius: 50% 50% 0 0;
  }
  
  .hero h1 {
    font-size: 2.25rem;
  }
  
  .hero-sub {
    font-size: 1.1rem;
  }
  
  .hero-actions {
    flex-direction: column;
  }
  
  .hero-actions .btn {
    width: 100%;
    justify-content: center;
  }
  
  .hero-stats {
    flex-wrap: wrap;
    gap: 24px;
  }
  
  .section-header h2 {
    font-size: 2rem;
  }
  
  .features {
    padding: 60px 0;
  }
  
  .features .grid {
    grid-template-columns: 1fr;
  }
  
  .cta {
    padding: 60px 0;
  }
  
  .cta h2 {
    font-size: 2rem;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 2rem;
  }
  
  .hero-badge {
    font-size: 0.8rem;
  }
  
  .section-header h2 {
    font-size: 1.75rem;
  }
}

/* Pricing Section */
.pricing-section {
  padding: 80px 0;
  background: var(--white);
}

.tab-nav {
  display: flex;
  justify-content: center;
  gap: 8px;
  background: var(--bg);
  padding: 6px;
  border-radius: 12px;
  max-width: 320px;
  margin: 0 auto 48px;
}

.tab-btn {
  flex: 1;
  padding: 12px 24px;
  border: none;
  background: transparent;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font-body);
}

.tab-btn.active {
  background: var(--white);
  color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.tab-btn:hover:not(.active) {
  color: var(--text);
}

.pricing-tabs.hidden {
  display: none;
}

.pricing-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 32px;
  max-width: 900px;
  margin: 0 auto;
}

.pricing-card {
  background: var(--white);
  border-radius: 20px;
  box-shadow: var(--shadow-md);
  border: 2px solid var(--border);
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.pricing-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
}

.pricing-card.featured {
  border-color: var(--primary);
  background: linear-gradient(180deg, var(--bg) 0%, var(--white) 30%);
}

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

.featured-badge {
  position: absolute;
  top: 16px;
  right: 16px;
  background: var(--cta);
  color: var(--white);
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 700;
}

.pricing-header {
  padding: 40px 32px 24px;
  text-align: center;
  border-bottom: 1px solid var(--border);
}

.pricing-header h3 {
  font-family: var(--font-heading);
  margin: 0 0 16px;
  font-size: 1.35rem;
  font-weight: 600;
  color: var(--text);
}

.price {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 8px;
}

.price .amount {
  font-family: var(--font-heading);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--primary);
}

.price .period {
  font-size: 1rem;
  color: var(--text-muted);
}

.price.academic-price .amount {
  color: var(--cta);
}

.pricing-features {
  padding: 24px 32px;
}

.pricing-features ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.pricing-features li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 12px 0;
  color: var(--text-light);
  font-size: 0.95rem;
  line-height: 1.5;
  border-bottom: 1px solid var(--border);
}

.pricing-features li:last-child {
  border-bottom: none;
}

.pricing-features li svg {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  color: var(--primary);
  margin-top: 2px;
}

.pricing-cta {
  padding: 0 32px 32px;
  text-align: center;
}

.pricing-cta .btn {
  width: 100%;
  justify-content: center;
}

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

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

/* Note Box */
.note-box {
  max-width: 900px;
  margin: 40px auto;
  padding: 24px;
  background: var(--bg);
  border-radius: 12px;
  border-left: 4px solid var(--primary);
}

.note-box p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* FAQ Section */
.faq-section {
  padding: 80px 0;
  background: var(--white);
}

.faq-section h2 {
  text-align: center;
  font-family: var(--font-heading);
  margin: 0 0 48px;
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--text);
}

.faq-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
  max-width: 1000px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg);
  padding: 24px;
  border-radius: 12px;
  border-left: 4px solid var(--primary);
}

.faq-item h3 {
  font-family: var(--font-heading);
  margin: 0 0 12px;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text);
}

.faq-item p {
  margin: 0;
  color: var(--text-muted);
  line-height: 1.6;
  font-size: 0.95rem;
}

/* Contact Section */
.contact-section {
  padding: 80px 0;
  background: var(--white);
}

.contact-wrapper {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 48px;
  align-items: start;
}

.contact-form {
  background: var(--white);
  padding: 40px;
  border-radius: 20px;
  box-shadow: var(--shadow-md);
  border: 2px solid var(--border);
}

.contact-form h2 {
  font-family: var(--font-heading);
  margin: 0 0 8px;
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text);
}

.form-desc {
  margin: 0 0 32px;
  color: var(--text-muted);
  font-size: 1rem;
}

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

.form-group label {
  display: block;
  margin-bottom: 8px;
  font-weight: 600;
  color: var(--text);
  font-size: 0.95rem;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 14px 18px;
  border: 2px solid var(--border);
  border-radius: 10px;
  font-size: 1rem;
  font-family: var(--font-body);
  transition: all var(--transition);
  background: var(--bg);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary);
  background: var(--white);
  box-shadow: 0 0 0 4px rgba(6, 150, 105, 0.1);
}

.form-group textarea {
  resize: vertical;
  min-height: 140px;
}

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

.contact-form .btn {
  width: 100%;
  justify-content: center;
  margin-top: 8px;
}

.contact-form .btn svg {
  width: 20px;
  height: 20px;
}

.form-msg {
  margin-top: 16px;
  padding: 16px;
  border-radius: 10px;
  font-weight: 600;
  text-align: center;
  display: none;
}

.form-msg.show {
  display: block;
}

.form-msg.success {
  background: rgba(6, 150, 105, 0.1);
  color: var(--primary);
  border: 1px solid var(--primary);
}

.form-msg.error {
  background: rgba(249, 115, 22, 0.1);
  color: var(--cta);
  border: 1px solid var(--cta);
}

/* Contact Info */
.contact-info {
  background: var(--bg);
  padding: 40px;
  border-radius: 20px;
}

.contact-info h2 {
  font-family: var(--font-heading);
  margin: 0 0 8px;
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text);
}

.info-desc {
  margin: 0 0 32px;
  color: var(--text-muted);
  font-size: 1rem;
}

.info-list {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.info-item {
  display: flex;
  gap: 16px;
}

.info-icon {
  width: 52px;
  height: 52px;
  background: var(--white);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  color: var(--primary);
}

.info-icon svg {
  width: 24px;
  height: 24px;
}

.info-content h3 {
  font-family: var(--font-heading);
  margin: 0 0 4px;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text);
}

.info-content p {
  margin: 0;
  color: var(--text-light);
  font-size: 1rem;
  font-weight: 500;
}

.info-content a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition);
}

.info-content a:hover {
  color: var(--primary-dark);
}

.info-note {
  display: block;
  margin-top: 4px;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* Responsive */
@media (max-width: 768px) {
  .pricing-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  
  .pricing-header {
    padding: 32px 24px 20px;
  }
  
  .pricing-features {
    padding: 20px 24px;
  }
  
  .pricing-cta {
    padding: 0 24px 24px;
  }
  
  .price .amount {
    font-size: 2rem;
  }
  
  .tab-btn {
    padding: 10px 16px;
    font-size: 0.9rem;
  }

  .contact-wrapper {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  
  .contact-form {
    padding: 28px;
  }
  
  .contact-info {
    padding: 28px;
  }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  .card {
    animation: none;
  }
  
  .btn,
  .card,
  .logo,
  .main-nav a {
    transition: none;
  }
}