/* ============================================
   颐笙健康官网 - 设计系统与全局样式
   ============================================ */

/* --- Google Fonts Import --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=Noto+Sans+SC:wght@300;400;500;600;700;900&display=swap');

/* --- CSS Custom Properties (Design Tokens) --- */
:root {
  /* Primary Palette */
  --color-bg-primary: #0a0f1a;
  --color-bg-secondary: #111827;
  --color-bg-card: rgba(17, 24, 39, 0.7);
  --color-bg-glass: rgba(255, 255, 255, 0.04);
  --color-bg-glass-hover: rgba(255, 255, 255, 0.08);

  /* Accent Colors */
  --color-accent-primary: #10b981;
  --color-accent-secondary: #06d6a0;
  --color-accent-tertiary: #3b82f6;
  --color-accent-warm: #f59e0b;
  --color-accent-rose: #f43f5e;
  --color-glow-green: rgba(16, 185, 129, 0.3);
  --color-glow-blue: rgba(59, 130, 246, 0.3);

  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #10b981 0%, #06d6a0 50%, #3b82f6 100%);
  --gradient-hero: linear-gradient(135deg, #0a0f1a 0%, #111827 40%, #0f2027 100%);
  --gradient-card: linear-gradient(145deg, rgba(16, 185, 129, 0.08), rgba(59, 130, 246, 0.05));
  --gradient-text: linear-gradient(90deg, #10b981, #06d6a0, #3b82f6);
  --gradient-border: linear-gradient(135deg, rgba(16, 185, 129, 0.5), rgba(59, 130, 246, 0.5));
  --gradient-glow: radial-gradient(ellipse at center, rgba(16, 185, 129, 0.15) 0%, transparent 70%);

  /* Text Colors */
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-tertiary: #64748b;
  --text-accent: #10b981;

  /* Typography */
  --font-primary: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  --font-size-6xl: 3.75rem;
  --font-size-hero: clamp(2.5rem, 5vw, 4.5rem);

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;
  --space-section: clamp(4rem, 8vw, 8rem);

  /* Border & Radius */
  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-full: 9999px;
  --border-glass: 1px solid rgba(255, 255, 255, 0.08);

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 10px 40px rgba(0, 0, 0, 0.5);
  --shadow-glow-green: 0 0 30px rgba(16, 185, 129, 0.2);
  --shadow-glow-blue: 0 0 30px rgba(59, 130, 246, 0.2);

  /* Transitions */
  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 0.6s cubic-bezier(0.34, 1.56, 0.64, 1);

  /* Layout */
  --max-width: 1280px;
  --nav-height: 80px;
}

/* --- Reset & Base --- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-primary);
  background-color: var(--color-bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
}

a {
  text-decoration: none;
  color: inherit;
  transition: color var(--transition-fast);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

ul, ol {
  list-style: none;
}

/* --- Utility Classes --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-xl);
}

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

.gradient-text {
  background: var(--gradient-text);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

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

.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }
.reveal-delay-5 { transition-delay: 0.5s; }

/* --- Background Decorative Elements --- */
.bg-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(100px);
  pointer-events: none;
  z-index: 0;
}

.bg-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
  background-size: 60px 60px;
  pointer-events: none;
  z-index: 0;
}

/* ============================================
   NAVIGATION
   ============================================ */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  z-index: 1000;
  transition: background var(--transition-base), box-shadow var(--transition-base), backdrop-filter var(--transition-base);
}

.navbar.scrolled {
  background: rgba(10, 15, 26, 0.85);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: var(--border-glass);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}

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

.nav-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--font-size-xl);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.nav-logo .logo-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  font-weight: 800;
  color: #fff;
  box-shadow: var(--shadow-glow-green);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-2xl);
}

.nav-links a {
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-secondary);
  position: relative;
  padding: var(--space-xs) 0;
  transition: color var(--transition-fast);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
  transition: width var(--transition-base);
}

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

.nav-links a:hover::after {
  width: 100%;
}

.nav-cta {
  padding: 0.6rem 1.5rem !important;
  background: var(--gradient-primary);
  border-radius: var(--radius-full);
  color: #fff !important;
  font-weight: 600 !important;
  font-size: var(--font-size-sm);
  box-shadow: var(--shadow-glow-green);
  transition: transform var(--transition-fast), box-shadow var(--transition-fast) !important;
}

.nav-cta::after {
  display: none !important;
}

.nav-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 40px rgba(16, 185, 129, 0.4);
}

/* Mobile Menu Toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 5px;
  z-index: 1001;
}

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

/* ============================================
   HERO SECTION
   ============================================ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--gradient-hero);
  overflow: hidden;
}

.hero .bg-glow.glow-1 {
  width: 600px;
  height: 600px;
  background: var(--color-glow-green);
  top: -200px;
  right: -100px;
  animation: float-glow 8s ease-in-out infinite;
}

.hero .bg-glow.glow-2 {
  width: 400px;
  height: 400px;
  background: var(--color-glow-blue);
  bottom: -100px;
  left: -100px;
  animation: float-glow 10s ease-in-out infinite reverse;
}

.hero .bg-glow.glow-3 {
  width: 300px;
  height: 300px;
  background: rgba(244, 63, 94, 0.1);
  top: 50%;
  left: 50%;
  animation: float-glow 12s ease-in-out infinite 2s;
}

@keyframes float-glow {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(30px, -30px) scale(1.1); }
  66% { transform: translate(-20px, 20px) scale(0.95); }
}

/* Animated particles */
.hero-particles {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

.particle {
  position: absolute;
  width: 3px;
  height: 3px;
  background: var(--color-accent-primary);
  border-radius: 50%;
  opacity: 0;
  animation: particle-rise linear infinite;
}

@keyframes particle-rise {
  0% {
    opacity: 0;
    transform: translateY(100vh) scale(0);
  }
  10% { opacity: 0.6; }
  90% { opacity: 0.2; }
  100% {
    opacity: 0;
    transform: translateY(-10vh) scale(1);
  }
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  max-width: 900px;
  padding: calc(var(--nav-height) + 2rem) var(--space-xl) var(--space-3xl);
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.5rem 1.2rem;
  background: var(--color-bg-glass);
  border: var(--border-glass);
  border-radius: var(--radius-full);
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-bottom: var(--space-xl);
  backdrop-filter: blur(10px);
  animation: fadeInDown 0.8s ease-out;
}

.hero-badge .badge-dot {
  width: 8px;
  height: 8px;
  background: var(--color-accent-primary);
  border-radius: 50%;
  animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
  0%, 100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.5); }
  50% { box-shadow: 0 0 0 8px rgba(16, 185, 129, 0); }
}

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

.hero h1 {
  font-size: var(--font-size-hero);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin-bottom: var(--space-lg);
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

.hero-subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--text-secondary);
  max-width: 650px;
  margin: 0 auto var(--space-2xl);
  line-height: 1.8;
  animation: fadeInUp 0.8s ease-out 0.4s both;
}

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

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-lg);
  flex-wrap: wrap;
  animation: fadeInUp 0.8s ease-out 0.6s both;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.85rem 2rem;
  font-family: var(--font-primary);
  font-size: var(--font-size-base);
  font-weight: 600;
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.btn-primary {
  background: var(--gradient-primary);
  color: #fff;
  box-shadow: var(--shadow-glow-green);
}

.btn-primary::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.2), transparent);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.btn-primary:hover {
  transform: translateY(-3px);
  box-shadow: 0 0 50px rgba(16, 185, 129, 0.4);
}

.btn-primary:hover::before {
  opacity: 1;
}

.btn-secondary {
  background: var(--color-bg-glass);
  color: var(--text-primary);
  border: var(--border-glass);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: var(--color-bg-glass-hover);
  transform: translateY(-3px);
  border-color: rgba(255, 255, 255, 0.15);
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: var(--space-3xl);
  margin-top: var(--space-4xl);
  animation: fadeInUp 0.8s ease-out 0.8s both;
}

.hero-stat {
  text-align: center;
}

.hero-stat .stat-number {
  font-size: var(--font-size-4xl);
  font-weight: 800;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  line-height: 1.2;
}

.hero-stat .stat-label {
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
  margin-top: var(--space-xs);
}

/* ============================================
   SECTION HEADERS
   ============================================ */
.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto var(--space-3xl);
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-accent-primary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-md);
}

.section-tag::before,
.section-tag::after {
  content: '';
  width: 20px;
  height: 1px;
  background: var(--color-accent-primary);
}

.section-header h2 {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.2;
  margin-bottom: var(--space-md);
}

.section-header p {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ============================================
   AHI INDEX SECTION
   ============================================ */
.ahi-section {
  position: relative;
  background: var(--color-bg-secondary);
  overflow: hidden;
}

.ahi-section .bg-glow {
  width: 500px;
  height: 500px;
  background: var(--color-glow-green);
  top: 50%;
  left: -200px;
  transform: translateY(-50%);
}

.ahi-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3xl);
  align-items: center;
}

.ahi-visual {
  position: relative;
}

.ahi-visual img {
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
}

.ahi-visual-placeholder {
  width: 100%;
  aspect-ratio: 4/3;
  border-radius: var(--radius-xl);
  background: var(--gradient-card);
  border: var(--border-glass);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

.ahi-visual-placeholder::before {
  content: '';
  position: absolute;
  inset: 0;
  background: 
    radial-gradient(circle at 30% 40%, rgba(16, 185, 129, 0.15), transparent 50%),
    radial-gradient(circle at 70% 60%, rgba(59, 130, 246, 0.1), transparent 50%);
}

.ahi-content h3 {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-bottom: var(--space-md);
}

.ahi-content .ahi-desc {
  color: var(--text-secondary);
  margin-bottom: var(--space-2xl);
  line-height: 1.9;
}

.ahi-metrics {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.metric-card {
  display: flex;
  gap: var(--space-lg);
  padding: var(--space-lg);
  background: var(--color-bg-glass);
  border: var(--border-glass);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(10px);
  transition: all var(--transition-base);
}

.metric-card:hover {
  background: var(--color-bg-glass-hover);
  border-color: rgba(16, 185, 129, 0.2);
  transform: translateX(8px);
}

.metric-icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.4rem;
}

.metric-icon.green { background: rgba(16, 185, 129, 0.15); }
.metric-icon.blue { background: rgba(59, 130, 246, 0.15); }
.metric-icon.amber { background: rgba(245, 158, 11, 0.15); }

.metric-info h4 {
  font-size: var(--font-size-base);
  font-weight: 600;
  margin-bottom: var(--space-xs);
}

.metric-info p {
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
  line-height: 1.6;
}

/* Stats Bar */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
  margin-top: var(--space-3xl);
  padding: var(--space-2xl);
  background: var(--color-bg-glass);
  border: var(--border-glass);
  border-radius: var(--radius-xl);
  backdrop-filter: blur(10px);
}

.stat-item {
  text-align: center;
  position: relative;
}

.stat-item:not(:last-child)::after {
  content: '';
  position: absolute;
  right: -0.75rem;
  top: 10%;
  height: 80%;
  width: 1px;
  background: rgba(255, 255, 255, 0.08);
}

.stat-item .stat-value {
  font-size: var(--font-size-4xl);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: var(--space-xs);
}

.stat-item .stat-value.green { color: var(--color-accent-primary); }
.stat-item .stat-value.blue { color: var(--color-accent-tertiary); }
.stat-item .stat-value.amber { color: var(--color-accent-warm); }

.stat-item .stat-desc {
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
}

/* ============================================
   SERVICES SECTION
   ============================================ */
.services-section {
  position: relative;
  overflow: hidden;
}

.services-section .bg-glow {
  width: 400px;
  height: 400px;
  background: var(--color-glow-blue);
  bottom: -100px;
  right: -100px;
}

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

.service-card {
  position: relative;
  padding: var(--space-2xl);
  background: var(--color-bg-glass);
  border: var(--border-glass);
  border-radius: var(--radius-xl);
  backdrop-filter: blur(10px);
  transition: all var(--transition-slow);
  overflow: hidden;
  cursor: default;
}

/* Animated gradient border on hover */
.service-card::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-xl);
  padding: 1px;
  background: var(--gradient-border);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0;
  transition: opacity var(--transition-base);
}

.service-card:hover::before {
  opacity: 1;
}

.service-card:hover {
  transform: translateY(-8px);
  background: var(--color-bg-glass-hover);
  box-shadow: var(--shadow-glow-green);
}

.service-card .card-number {
  font-size: var(--font-size-5xl);
  font-weight: 900;
  background: linear-gradient(180deg, rgba(255,255,255,0.08), transparent);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  position: absolute;
  top: var(--space-md);
  right: var(--space-lg);
  line-height: 1;
}

.service-card .card-icon {
  width: 56px;
  height: 56px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: var(--space-lg);
  position: relative;
  z-index: 1;
}

.card-icon.icon-green { background: rgba(16, 185, 129, 0.12); color: var(--color-accent-primary); }
.card-icon.icon-blue { background: rgba(59, 130, 246, 0.12); color: var(--color-accent-tertiary); }
.card-icon.icon-amber { background: rgba(245, 158, 11, 0.12); color: var(--color-accent-warm); }
.card-icon.icon-rose { background: rgba(244, 63, 94, 0.12); color: var(--color-accent-rose); }
.card-icon.icon-teal { background: rgba(6, 214, 160, 0.12); color: var(--color-accent-secondary); }
.card-icon.icon-purple { background: rgba(139, 92, 246, 0.12); color: #8b5cf6; }

.service-card h3 {
  font-size: var(--font-size-xl);
  font-weight: 700;
  margin-bottom: var(--space-md);
  position: relative;
  z-index: 1;
}

.service-card p {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  line-height: 1.8;
  position: relative;
  z-index: 1;
}

.service-card .card-cta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  margin-top: var(--space-lg);
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--color-accent-primary);
  position: relative;
  z-index: 1;
  transition: gap var(--transition-fast);
}

.service-card:hover .card-cta {
  gap: var(--space-md);
}

/* ============================================
   ADVANTAGES SECTION
   ============================================ */
.advantages-section {
  position: relative;
  background: var(--color-bg-secondary);
  overflow: hidden;
}

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

.advantage-card {
  padding: var(--space-2xl);
  background: var(--color-bg-glass);
  border: var(--border-glass);
  border-radius: var(--radius-xl);
  text-align: center;
  backdrop-filter: blur(10px);
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.advantage-card::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

.advantage-card:hover {
  transform: translateY(-6px);
  background: var(--color-bg-glass-hover);
}

.advantage-card:hover::after {
  transform: scaleX(1);
}

.advantage-card .adv-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto var(--space-lg);
  border-radius: var(--radius-lg);
  background: rgba(16, 185, 129, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  transition: transform var(--transition-spring);
}

.advantage-card:hover .adv-icon {
  transform: scale(1.15) rotate(5deg);
}

.advantage-card h3 {
  font-size: var(--font-size-lg);
  font-weight: 700;
  margin-bottom: var(--space-sm);
}

.advantage-card p {
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
  line-height: 1.7;
}

/* ============================================
   SOLUTIONS SECTION (8大体系)
   ============================================ */
.solutions-section {
  position: relative;
  overflow: hidden;
}

.solutions-intro {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-3xl);
  align-items: center;
  margin-bottom: var(--space-3xl);
}

.solutions-intro h3 {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-bottom: var(--space-md);
}

.solutions-intro p {
  color: var(--text-secondary);
  line-height: 1.9;
}

.solutions-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
}

.solution-item {
  padding: var(--space-xl);
  background: var(--color-bg-glass);
  border: var(--border-glass);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(10px);
  transition: all var(--transition-base);
  text-align: center;
}

.solution-item:hover {
  background: var(--color-bg-glass-hover);
  border-color: rgba(16, 185, 129, 0.15);
  transform: translateY(-4px);
}

.solution-item .sol-num {
  font-size: var(--font-size-2xl);
  font-weight: 800;
  color: var(--color-accent-primary);
  margin-bottom: var(--space-sm);
  opacity: 0.6;
}

.solution-item h4 {
  font-size: var(--font-size-base);
  font-weight: 600;
}

/* ============================================
   BENEFITS SECTION (价值体系)
   ============================================ */
.benefits-section {
  position: relative;
  background: var(--color-bg-secondary);
  overflow: hidden;
}

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

.benefit-card {
  padding: var(--space-2xl);
  border-radius: var(--radius-xl);
  background: var(--gradient-card);
  border: var(--border-glass);
  transition: all var(--transition-base);
  position: relative;
}

.benefit-card:hover {
  transform: translateY(-4px);
  border-color: rgba(16, 185, 129, 0.2);
}

.benefit-card .benefit-emoji {
  font-size: 2rem;
  margin-bottom: var(--space-md);
}

.benefit-card h3 {
  font-size: var(--font-size-lg);
  font-weight: 700;
  margin-bottom: var(--space-xs);
}

.benefit-card .benefit-sub {
  font-size: var(--font-size-sm);
  color: var(--color-accent-primary);
  font-weight: 500;
}

/* ============================================
   CTA SECTION
   ============================================ */
.cta-section {
  position: relative;
  padding: var(--space-section) 0;
  overflow: hidden;
}

.cta-box {
  position: relative;
  padding: var(--space-4xl);
  border-radius: var(--radius-xl);
  background: var(--gradient-card);
  border: var(--border-glass);
  text-align: center;
  overflow: hidden;
}

.cta-box::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 50% 0%, rgba(16, 185, 129, 0.15), transparent 60%);
}

.cta-box h2 {
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  font-weight: 800;
  margin-bottom: var(--space-md);
  position: relative;
  z-index: 1;
}

.cta-box p {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  margin-bottom: var(--space-2xl);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
  position: relative;
  z-index: 1;
}

.cta-box .btn {
  position: relative;
  z-index: 1;
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
  background: var(--color-bg-secondary);
  border-top: var(--border-glass);
  padding: var(--space-3xl) 0 var(--space-xl);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: var(--space-3xl);
  margin-bottom: var(--space-3xl);
}

.footer-brand .footer-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--font-size-xl);
  font-weight: 700;
  margin-bottom: var(--space-md);
}

.footer-brand .footer-logo .logo-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: var(--gradient-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  font-weight: 800;
  color: #fff;
}

.footer-brand .footer-desc {
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
  line-height: 1.8;
  max-width: 320px;
}

.footer-col h4 {
  font-size: var(--font-size-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-secondary);
  margin-bottom: var(--space-lg);
}

.footer-col a {
  display: block;
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
  padding: var(--space-xs) 0;
  transition: color var(--transition-fast), transform var(--transition-fast);
}

.footer-col a:hover {
  color: var(--color-accent-primary);
  transform: translateX(4px);
}

.footer-contact-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
  margin-bottom: var(--space-md);
  line-height: 1.6;
}

.footer-contact-item .contact-icon {
  flex-shrink: 0;
  margin-top: 2px;
  color: var(--color-accent-primary);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-xl);
  border-top: var(--border-glass);
  font-size: var(--font-size-xs);
  color: var(--text-tertiary);
}

.footer-slogan {
  font-style: italic;
  color: var(--text-accent);
}

/* ============================================
   SCROLL TO TOP BUTTON
   ============================================ */
.scroll-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--color-bg-glass);
  border: var(--border-glass);
  backdrop-filter: blur(10px);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-primary);
  font-size: 1.2rem;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: all var(--transition-base);
  z-index: 900;
}

.scroll-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.scroll-top:hover {
  background: var(--color-accent-primary);
  box-shadow: var(--shadow-glow-green);
  transform: translateY(-3px);
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */
@media (max-width: 1024px) {
  .ahi-grid,
  .solutions-intro {
    grid-template-columns: 1fr;
  }

  .solutions-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .services-grid,
  .advantages-grid,
  .benefits-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  :root {
    --nav-height: 64px;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: rgba(10, 15, 26, 0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    justify-content: center;
    gap: var(--space-xl);
    padding: var(--space-2xl);
    transition: right var(--transition-base);
    border-left: var(--border-glass);
  }

  .nav-links.open {
    right: 0;
  }

  .nav-toggle {
    display: flex;
  }

  .hero-stats {
    gap: var(--space-xl);
  }

  .hero-stat .stat-number {
    font-size: var(--font-size-2xl);
  }

  .services-grid,
  .advantages-grid,
  .solutions-grid,
  .benefits-grid {
    grid-template-columns: 1fr;
  }

  .stats-bar {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }

  .stat-item:not(:last-child)::after {
    display: none;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .footer-bottom {
    flex-direction: column;
    gap: var(--space-sm);
  }

  .cta-box {
    padding: var(--space-2xl);
  }
}

@media (max-width: 480px) {
  .hero-actions {
    flex-direction: column;
  }

  .hero-stats {
    flex-direction: column;
    gap: var(--space-lg);
  }
}