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

:root {
  --bg-deep: #062166;
  --bg-hero: linear-gradient(135deg, #0a1a3a 0%, #0d2b5e 40%, #0a3a6e 70%, #0a4a7a 100%);
  --bg-light: #f4f6f8;
  --text-primary: #f0f4f8;
  --text-secondary: rgba(240, 244, 248, 0.72);
  --text-muted: rgba(240, 244, 248, 0.42);
  --text-dark: #1a2332;
  --text-dark-secondary: #4a5568;
  --accent: #5eb8ff;
  --accent-glow: rgba(94, 184, 255, 0.35);
  --glass-bg: rgba(255, 255, 255, 0.08);
  --glass-border: rgba(255, 255, 255, 0.12);
  --glass-bg-light: rgba(255, 255, 255, 0.72);
  --glass-border-light: rgba(255, 255, 255, 0.5);
  --font-sans: "SF Pro Display", "SF Pro Text", "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

body {
  font-family: var(--font-sans);
  color: var(--text-primary);
  background: var(--bg-deep);
  min-height: 100vh;
  overflow-x: hidden;
}

/* ===== Molecule Background Canvas ===== */
#molecule-bg {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

/* ===== Top Navigation ===== */
.top-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 clamp(20px, 4vw, 48px);
  height: 72px;
  background: transparent;
  transition: background 0.4s ease, backdrop-filter 0.4s ease;
}

.top-nav.scrolled {
  background: linear-gradient(90deg, #0a1a3a 0%, #0d2b5e 40%, #0a3a6e 70%, #0a4a7a 100%);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}

.nav-logo img {
  height: 44px;
  width: auto;
  display: block;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: clamp(24px, 3vw, 40px);
}

.nav-links a {
  font-size: 0.82rem;
  font-weight: 400;
  letter-spacing: 0.06em;
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.3s ease;
  position: relative;
}

.nav-links a::after {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 100%;
  height: 1px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.35s ease;
}

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

.nav-links a:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.nav-cta {
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--text-primary);
  text-decoration: none;
  padding: 8px 20px;
  border: 1px solid var(--glass-border);
  border-radius: 6px;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  transition: background 0.3s ease, border-color 0.3s ease;
}

.nav-cta:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: rgba(255, 255, 255, 0.25);
}

.mobile-menu-btn {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 6px;
  width: 48px;
  height: 48px;
  background: rgba(94, 184, 255, 0.15);
  border: 2px solid rgba(255, 255, 255, 0.35);
  border-radius: 10px;
  cursor: pointer;
  padding: 0;
  z-index: 110;
  outline: none;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

.mobile-menu-btn:active {
  background: rgba(94, 184, 255, 0.3);
}

.mobile-menu-btn span {
  display: block;
  width: 28px;
  height: 3px;
  background: #ffffff;
  border-radius: 3px;
  transition: all 0.3s ease;
}

.mobile-menu-btn.active span:nth-child(1) {
  transform: translateY(9px) rotate(45deg);
}

.mobile-menu-btn.active span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.mobile-menu-btn.active span:nth-child(3) {
  transform: translateY(-9px) rotate(-45deg);
}

.mobile-nav-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(8px);
  z-index: 95;
  opacity: 0;
  visibility: hidden;
  transition: all 0.35s ease;
}

.mobile-nav-overlay.active {
  opacity: 1;
  visibility: visible;
}

/* ===== Hero Section ===== */
.hero {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  display: flex;
  align-items: center;
  background: var(--bg-hero);
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 70% 50%, rgba(94, 184, 255, 0.12) 0%, transparent 60%);
  pointer-events: none;
}

.hero-inner {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 clamp(24px, 5vw, 60px);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(40px, 6vw, 80px);
  align-items: center;
  min-height: 100vh;
}

.hero-content {
  animation: fadeInUp 1s ease-out both;
}

.hero-tag {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: clamp(16px, 2.5vh, 24px);
  padding: 6px 14px;
  border: 1px solid rgba(94, 184, 255, 0.25);
  border-radius: 4px;
  background: rgba(94, 184, 255, 0.08);
}

.hero-title {
  font-size: clamp(2rem, 4.5vw, 3.4rem);
  font-weight: 300;
  letter-spacing: 0.02em;
  line-height: 1.2;
  color: var(--text-primary);
  margin-bottom: clamp(12px, 2vh, 20px);
}

.hero-subtitle-cn {
  font-size: clamp(1.4rem, 2.6vw, 1.9rem);
  font-weight: 300;
  line-height: 1.5;
  color: var(--accent);
  margin-bottom: clamp(28px, 4vh, 40px);
  max-width: 480px;
  letter-spacing: 0.06em;
}

.hero-cta-group {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  color: var(--text-primary);
  text-decoration: none;
  padding: 12px 28px;
  border-radius: 6px;
  background: linear-gradient(135deg, rgba(94, 184, 255, 0.25), rgba(94, 184, 255, 0.1));
  border: 1px solid rgba(94, 184, 255, 0.35);
  backdrop-filter: blur(8px);
  transition: all 0.35s ease;
}

.btn-primary:hover {
  background: linear-gradient(135deg, rgba(94, 184, 255, 0.4), rgba(94, 184, 255, 0.2));
  border-color: rgba(94, 184, 255, 0.55);
  box-shadow: 0 8px 32px rgba(94, 184, 255, 0.2);
  transform: translateY(-1px);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  font-weight: 400;
  letter-spacing: 0.04em;
  color: var(--text-secondary);
  text-decoration: none;
  padding: 12px 28px;
  border-radius: 6px;
  border: 1px solid var(--glass-border);
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  transition: all 0.35s ease;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.12);
  color: var(--text-primary);
  transform: translateY(-1px);
}

/* ===== Hero Visual ===== */
.hero-visual {
  position: absolute;
  right: 0;
  top: 0;
  bottom: 0;
  width: 50vw;
  display: flex;
  align-items: center;
  justify-content: center;
  animation: fadeInUp 1s ease-out 0.2s both;
  overflow: visible;
  pointer-events: none;
}

.hero-molecule-img {
  height: 100vh;
  width: auto;
  max-width: none;
  opacity: 0.10;
  display: block;
  object-fit: cover;
  object-position: center;
  filter: drop-shadow(0 0 40px rgba(94, 184, 255, 0.15));
  transform: translateX(20px);
}

/* ===== Light Section (Swiss style transition) ===== */
.light-section {
  position: relative;
  z-index: 1;
  background: var(--bg-light);
  padding: clamp(40px, 6vh, 60px) clamp(24px, 5vw, 60px);
}

.light-section::before {
  content: "";
  position: absolute;
  top: -120px;
  left: 0;
  right: 0;
  height: 120px;
  background: linear-gradient(to bottom, transparent, var(--bg-light));
  pointer-events: none;
}

.section-inner {
  max-width: 1280px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: clamp(40px, 6vh, 64px);
}

.section-header .section-label {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-dark-secondary);
  margin-bottom: 12px;
}

.section-header .section-title {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 300;
  letter-spacing: 0.01em;
  color: var(--text-dark);
}

/* ===== Value Cards ===== */
.value-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: clamp(16px, 2vw, 24px);
}

.value-card {
  background: rgba(255, 255, 255, 0.6);
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-radius: 12px;
  padding: clamp(24px, 3vw, 32px);
  backdrop-filter: blur(16px);
  transition: transform 0.4s ease, box-shadow 0.4s ease;
}

.value-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.08);
}

.value-card .card-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: linear-gradient(135deg, rgba(94, 184, 255, 0.15), rgba(94, 184, 255, 0.05));
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  object-fit: contain;
  padding: 6px;
}

.value-card h3 {
  font-size: 1rem;
  font-weight: 500;
  color: var(--text-dark);
  margin-bottom: 8px;
  letter-spacing: 0.01em;
}

.value-card p {
  font-size: 0.88rem;
  font-weight: 300;
  line-height: 1.65;
  color: var(--text-dark-secondary);
}

/* ===== Footer ===== */
.site-footer {
  position: relative;
  z-index: 1;
  background: var(--bg-hero);
  padding: clamp(26px, 4vh, 38px) clamp(24px, 5vw, 60px);
  text-align: center;
}

.footer-inner {
  max-width: 1280px;
  margin: 0 auto;
}

.footer-brand {
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.footer-copy {
  font-size: 0.75rem;
  font-weight: 300;
  color: rgba(240, 244, 248, 0.55);
  letter-spacing: 0.04em;
}

/* ===== About Page ===== */
.about-hero {
  position: relative;
  z-index: 1;
  min-height: 60vh;
  display: flex;
  align-items: flex-start;
  background: linear-gradient(to bottom,
    #0a1a3a 0%,
    #0d2b5e 50%,
    #1a488c 75%,
    #3c90d4 90%,
    #80c0e8 95%,
    #d8eaf5 98%,
    #f4f6f8 100%
  );
  padding-top: 120px;
  padding-bottom: 40px;
}

.about-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 30% 50%, rgba(94, 184, 255, 0.1) 0%, transparent 55%);
  pointer-events: none;
}

.about-hero-inner {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 clamp(24px, 5vw, 60px);
  position: relative;
}

.about-hero-content {
  max-width: 720px;
  animation: fadeInUp 0.9s ease-out both;
  padding-top: 20px;
}

.about-hero-content .section-label {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 16px;
}

.about-hero-content h1 {
  font-size: clamp(1.8rem, 3.5vw, 2.6rem);
  font-weight: 300;
  line-height: 1.3;
  color: var(--text-primary);
  margin-bottom: 20px;
}

.about-hero-content p {
  font-size: clamp(0.95rem, 1.4vw, 1.1rem);
  font-weight: 300;
  line-height: 1.75;
  color: var(--text-secondary);
}

/* ===== Animations ===== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(28px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes float {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-12px);
  }
}

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .hero-inner {
    grid-template-columns: 1fr;
    text-align: center;
    padding-top: 100px;
  }

  .hero-subtitle {
    margin-left: auto;
    margin-right: auto;
  }

  .hero-cta-group {
    justify-content: center;
  }

  .hero-visual {
    order: -1;
    max-width: 320px;
    margin: 0 auto;
  }

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

  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 75%;
    max-width: 280px;
    height: 100vh;
    background: linear-gradient(180deg, #0a1a3a 0%, #0d2b5e 100%);
    flex-direction: column;
    padding: 80px 30px 30px;
    gap: 28px;
    transition: right 0.35s ease;
    z-index: 105;
    box-shadow: -8px 0 32px rgba(0, 0, 0, 0.3);
  }

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

  .nav-links a {
    font-size: 1rem;
    padding: 12px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  }

  .nav-links a::after {
    display: none;
  }

  .mobile-menu-btn {
    display: flex;
  }
}

@media (max-width: 980px) {
  .value-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.6rem;
  }

  .btn-primary,
  .btn-secondary {
    width: 100%;
    justify-content: center;
  }

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