/* ============================================================
   因博科技 - 视觉增强样式表 (基于 Frontend Design Philosophy)
   保护所有 GEO 优化内容和 SEO 关键信息
   ============================================================ */

/* === 1. Typography Enhancement === */
/* 使用更 distinctive 的字体组合 */
@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@300;400;500;700;900&family=Space+Grotesk:wght@400;500;600;700&display=swap');

:root {
  /* === 2. Color System - 60-30-10 Rule === */
  --bg-primary: #ffffff;
  --bg-secondary: #f8faff;
  --bg-tertiary: #eff6ff;
  --text-primary: #1a1a2e;
  --text-secondary: #4a5568;
  --text-tertiary: #718096;
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --accent-subtle: rgba(37, 99, 235, 0.1);
  --orange: #ea580c;
  --orange-hover: #c2410c;
  --orange-subtle: rgba(234, 88, 12, 0.1);
  --success: #10b981;
  --warning: #f59e0b;
  --error: #ef4444;
  --border: #e2e8f0;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.12);
  --radius: 16px;
  --radius-sm: 8px;
  --radius-lg: 24px;
}

/* === 3. Background Atmosphere === */
/* 添加 subtle grain texture 和 gradient mesh */
body {
  font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
  color: var(--text-primary);
  background: var(--bg-primary);
  position: relative;
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 400 400' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
  opacity: 0.02;
  pointer-events: none;
  z-index: 9999;
}

/* === 4. Typography Hierarchy === */
h1, h2, h3, h4, h5, h6 {
  font-family: 'Space Grotesk', 'Noto Sans SC', sans-serif;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

h1 { font-size: clamp(2rem, 5vw, 3.5rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 2vw, 1.75rem); }

p {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-secondary);
}

/* === 5. Card Enhancement === */
/* 更精致的卡片设计 */
.card, .feature-card, .brand-card, .faq-item {
  background: var(--bg-primary);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  padding: 24px;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
}

.card:hover, .feature-card:hover, .brand-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--accent);
}

/* === 6. Button Enhancement === */
.btn, .submit-btn, .cta-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.95rem;
  transition: all 0.2s ease;
  cursor: pointer;
  border: none;
  text-decoration: none;
}

.btn-primary, .submit-btn {
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-hover) 100%);
  color: #fff;
  box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.btn-primary:hover, .submit-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(37, 99, 235, 0.4);
}

.btn-orange {
  background: linear-gradient(135deg, var(--orange) 0%, var(--orange-hover) 100%);
  color: #fff;
  box-shadow: 0 4px 12px rgba(234, 88, 12, 0.3);
}

.btn-orange:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(234, 88, 12, 0.4);
}

/* === 7. Animation Enhancement === */
/* Orchestrated page load animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.animate-fade-in-up {
  animation: fadeInUp 0.6s ease-out both;
}

.animate-fade-in {
  animation: fadeIn 0.6s ease-out both;
}

.animate-scale-in {
  animation: scaleIn 0.6s ease-out both;
}

/* Staggered delays */
.delay-100 { animation-delay: 0.1s; }
.delay-200 { animation-delay: 0.2s; }
.delay-300 { animation-delay: 0.3s; }
.delay-400 { animation-delay: 0.4s; }
.delay-500 { animation-delay: 0.5s; }

/* === 8. Gradient Mesh Backgrounds === */
.gradient-mesh {
  background: 
    radial-gradient(at 40% 20%, hsla(220, 100%, 74%, 0.15) 0px, transparent 50%),
    radial-gradient(at 80% 0%, hsla(189, 100%, 56%, 0.1) 0px, transparent 50%),
    radial-gradient(at 0% 50%, hsla(220, 100%, 93%, 0.15) 0px, transparent 50%);
}

/* === 9. Glassmorphism Effect === */
.glass {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
}

/* === 10. Enhanced Section Styling === */
section {
  position: relative;
}

.section-title {
  text-align: center;
  margin-bottom: 48px;
}

.section-title h2 {
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 12px;
  position: relative;
  display: inline-block;
}

.section-title h2::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 4px;
  background: linear-gradient(135deg, var(--accent) 0%, var(--orange) 100%);
  border-radius: 2px;
}

.section-title p {
  font-size: 1.1rem;
  color: var(--text-tertiary);
  max-width: 600px;
  margin: 0 auto;
}

/* === 11. FAQ Section Enhancement === */
.faq-section {
  background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
  padding: 80px 0;
}

.faq-item {
  background: var(--bg-primary);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 16px;
  border: 1px solid var(--border);
  transition: all 0.3s ease;
}

.faq-item:hover {
  box-shadow: var(--shadow);
  border-color: var(--accent);
}

/* === 12. Stats Banner Enhancement === */
.stats-banner {
  background: linear-gradient(135deg, #1e3a5f 0%, #2563eb 100%);
  position: relative;
  overflow: hidden;
}

.stats-banner::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: 
    radial-gradient(circle at 20% 50%, rgba(255,255,255,0.1) 0%, transparent 50%),
    radial-gradient(circle at 80% 50%, rgba(255,255,255,0.08) 0%, transparent 50%);
}

/* === 13. Comparison Table Enhancement === */
.comparison-section table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-primary);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.comparison-section thead {
  background: linear-gradient(135deg, var(--accent) 0%, #1e3a5f 100%);
  color: #fff;
}

.comparison-section th {
  padding: 16px 20px;
  text-align: left;
  font-weight: 600;
}

.comparison-section td {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  color: var(--text-secondary);
}

.comparison-section tr:nth-child(even) {
  background: var(--bg-secondary);
}

/* === 14. Credentials Bar Enhancement === */
.credentials-bar {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: 32px 0;
}

/* === 15. Source Citations Enhancement === */
.source-citations {
  background: var(--bg-secondary);
  padding: 48px 0;
  border-top: 1px solid var(--border);
}

.source-citations .citation-card {
  background: var(--bg-primary);
  border-radius: var(--radius);
  padding: 24px;
  border: 1px solid var(--border);
  transition: all 0.3s ease;
}

.source-citations .citation-card:hover {
  box-shadow: var(--shadow);
  transform: translateY(-2px);
}

/* === 16. Updated Badge Enhancement === */
.updated-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  background: var(--accent-subtle);
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin: 16px 0;
}

.updated-badge .badge-new {
  padding: 4px 8px;
  background: var(--success);
  color: #fff;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
}

/* === 17. Footer Enhancement === */
footer {
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
  color: #fff;
  padding: 60px 0 30px;
}

footer a {
  color: rgba(255, 255, 255, 0.7);
  transition: color 0.2s ease;
}

footer a:hover {
  color: #fff;
}

/* === 18. Navigation Enhancement === */
.navbar {
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: 16px 0;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  transition: all 0.3s ease;
}

.navbar.scrolled {
  box-shadow: var(--shadow);
}

/* === 19. Mobile Responsiveness === */
@media (max-width: 768px) {
  h1 { font-size: 2rem; }
  h2 { font-size: 1.5rem; }
  h3 { font-size: 1.25rem; }
  
  .section-title {
    margin-bottom: 32px;
  }
  
  .faq-section,
  .source-citations,
  .comparison-section {
    padding: 48px 0;
  }
  
  .stats-banner .container > div {
    grid-template-columns: repeat(2, 1fr) !important;
    gap: 24px !important;
  }
}

@media (max-width: 480px) {
  h1 { font-size: 1.75rem; }
  h2 { font-size: 1.25rem; }
  
  .stats-banner .container > div {
    grid-template-columns: 1fr !important;
  }
}

/* === 20. Scroll Reveal Animation === */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}