/* ============================================
   C2PA Tools - Landing Page Styles
   落地页专用样式
   ============================================ */

/* ============================================
   Header
   ============================================ */

.header {
  background-color: #ffffff;
  border-bottom: 1px solid var(--gray-200);
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--gray-900);
  text-decoration: none;
}

.logo-icon {
  width: 32px;
  height: 32px;
  color: var(--primary-600);
}

.nav {
  display: flex;
  align-items: center;
  gap: var(--space-6);
}

.nav-link {
  color: var(--gray-600);
  text-decoration: none;
  font-size: 0.875rem;
  transition: color var(--transition-fast);
}

.nav-link:hover {
  color: var(--gray-900);
}

/* ============================================
   Hero Section
   ============================================ */

.hero {
  padding: var(--space-16) 0;
  text-align: center;
}

.hero-title {
  font-size: 3rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: var(--space-6);
  line-height: 1.1;
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--gray-600);
  margin-bottom: var(--space-8);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.hero-actions {
  display: flex;
  gap: var(--space-4);
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: var(--space-12);
}

.hero-image {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  margin: 0 auto;
}

.hero-demo-image {
  max-width: 1200px;
  margin: 0 auto;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-2xl);
  background: white;
}

.demo-screenshot {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-lg);
  transition: transform 0.3s ease;
}

.hero-demo-image:hover .demo-screenshot {
  transform: scale(1.02);
}

/* ============================================
   What is C2PA Section
   ============================================ */

.c2pa-intro {
  padding: var(--space-16) 0;
  background-color: #ffffff;
}

.section-title {
  font-size: 2.25rem;
  font-weight: 700;
  text-align: center;
  color: var(--gray-900);
  margin-bottom: var(--space-4);
}

.section-description {
  font-size: 1.125rem;
  color: var(--gray-600);
  text-align: center;
  max-width: 800px;
  margin: 0 auto var(--space-12);
  line-height: 1.7;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-6);
  margin-top: var(--space-12);
}

.feature-card {
  text-align: center;
  padding: var(--space-6);
}

.feature-icon {
  width: 48px;
  height: 48px;
  color: var(--primary-600);
  margin: 0 auto var(--space-4);
}

.feature-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--gray-900);
  margin-bottom: var(--space-2);
}

.feature-description {
  font-size: 0.875rem;
  color: var(--gray-600);
  line-height: 1.6;
}

/* ============================================
   Before & After Section
   ============================================ */

.before-after {
  padding: var(--space-16) 0;
}

.comparison-container {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: var(--space-12);
  align-items: center;
  margin-top: var(--space-12);
}

.comparison-item {
  text-align: center;
}

.comparison-image-wrapper {
  position: relative;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: var(--space-4);
  background-color: var(--gray-100);
}

.comparison-image-placeholder {
  width: 100%;
  aspect-ratio: 4/3;
  background: linear-gradient(135deg, var(--gray-100) 0%, var(--gray-200) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gray-400);
  font-size: 1.25rem;
}

.comparison-image {
  width: 100%;
  height: auto;
  display: block;
  transition: transform 0.3s ease;
}

.comparison-image-wrapper:hover .comparison-image {
  transform: scale(1.02);
}

.comparison-label {
  position: absolute;
  top: var(--space-4);
  left: var(--space-4);
  background-color: rgba(0, 0, 0, 0.7);
  color: #ffffff;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-default);
  font-size: 0.875rem;
  font-weight: 500;
}

.comparison-arrow {
  width: 32px;
  height: 32px;
  color: var(--gray-400);
}

.comparison-meta {
  font-size: 0.875rem;
  color: var(--gray-600);
}

/* ============================================
   Features Section
   ============================================ */

.features {
  padding: var(--space-16) 0;
  background-color: #ffffff;
}

.features-grid-large {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: var(--space-6);
  margin-top: var(--space-12);
}

.feature-card-large {
  background-color: #ffffff;
  border: 1px solid var(--gray-200);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  transition: all var(--transition-base);
}

.feature-card-large:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-4px);
}

.feature-icon-large {
  width: 40px;
  height: 40px;
  color: var(--primary-600);
  margin-bottom: var(--space-4);
}

.feature-card-large .feature-title {
  margin-bottom: var(--space-2);
}

.feature-card-large .feature-description {
  line-height: 1.6;
}

/* ============================================
   CTA Section
   ============================================ */

.cta-section {
  padding: var(--space-16) 0;
  background: linear-gradient(135deg, var(--primary-600) 0%, var(--primary-700) 100%);
  color: #ffffff;
  text-align: center;
}

.cta-title {
  font-size: 2.25rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: var(--space-4);
}

.cta-description {
  font-size: 1.125rem;
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: var(--space-8);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.cta-actions {
  display: flex;
  gap: var(--space-4);
  justify-content: center;
  flex-wrap: wrap;
}

.btn-white {
  background-color: #ffffff;
  color: var(--primary-600);
}

.btn-white:hover {
  background-color: var(--gray-100);
}

/* ============================================
   Footer
   ============================================ */

.footer {
  background-color: var(--gray-100);
  padding: var(--space-12) 0;
  text-align: center;
}

.footer-content {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  align-items: center;
}

.footer-links {
  display: flex;
  gap: var(--space-6);
  flex-wrap: wrap;
  justify-content: center;
}

.footer-link {
  color: var(--gray-600);
  text-decoration: none;
  font-size: 0.875rem;
  transition: color var(--transition-fast);
}

.footer-link:hover {
  color: var(--gray-900);
}

.footer-text {
  font-size: 0.875rem;
  color: var(--gray-500);
}

/* ============================================
   响应式设计
   ============================================ */

@media (max-width: 768px) {
  .hero-title {
    font-size: 2rem;
  }

  .hero-subtitle {
    font-size: 1rem;
  }

  .hero {
    padding: var(--space-12) 0;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .section-description {
    font-size: 1rem;
  }

  .c2pa-intro,
  .before-after,
  .features,
  .cta-section {
    padding: var(--space-12) 0;
  }

  .comparison-container {
    grid-template-columns: 1fr;
    gap: var(--space-6);
  }

  .comparison-arrow {
    transform: rotate(90deg);
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .features-grid-large {
    grid-template-columns: 1fr;
  }

  .cta-title {
    font-size: 1.75rem;
  }

  .cta-description {
    font-size: 1rem;
  }

  .nav {
    gap: var(--space-4);
  }

  .nav-link {
    font-size: 0.75rem;
  }

  .hero-actions,
  .cta-actions {
    flex-direction: column;
    width: 100%;
  }

  .hero-actions .btn,
  .cta-actions .btn {
    width: 100%;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.75rem;
  }

  .section-title {
    font-size: 1.5rem;
  }

  .cta-title {
    font-size: 1.5rem;
  }

  .footer-links {
    flex-direction: column;
    gap: var(--space-3);
  }
}