:root {
  --page: #fbfcfb;
  --surface: #ffffff;
  --surface-muted: #f3f7f4;
  --ink: #172520;
  --ink-soft: #2a3c35;
  --muted: #62706a;
  --quiet: #7d8983;
  --line: #dfe8e2;
  --line-strong: #c8d8ce;
  --accent: #245c4c;
  --accent-soft: #e6f0ea;
  --graphite: #2f3331;
  --clay: #8b6f57;
  --shadow: 0 24px 80px rgba(23, 37, 32, 0.11);
  color-scheme: light;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--page);
  color: var(--ink);
  font-family:
    "Noto Sans SC",
    "PingFang SC",
    "Microsoft YaHei",
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    sans-serif;
  letter-spacing: 0;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  content: "";
  background:
    linear-gradient(90deg, rgba(36, 92, 76, 0.035) 1px, transparent 1px),
    linear-gradient(180deg, rgba(36, 92, 76, 0.025) 1px, transparent 1px);
  background-size: 72px 72px;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.75), transparent 70%);
}

a {
  color: inherit;
  text-decoration: none;
}

a:hover {
  color: var(--accent);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: 18px clamp(20px, 4vw, 56px);
  border-bottom: 1px solid rgba(223, 232, 226, 0.86);
  background: rgba(251, 252, 251, 0.92);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: max-content;
  color: var(--ink);
  font-size: 18px;
  font-weight: 750;
}

.brand-mark {
  width: 22px;
  height: 22px;
  border: 1px solid var(--accent);
  border-radius: 50%;
  background:
    linear-gradient(90deg, transparent 47%, var(--accent) 48%, var(--accent) 52%, transparent 53%),
    linear-gradient(0deg, transparent 47%, var(--accent) 48%, var(--accent) 52%, transparent 53%);
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 10px 22px;
  color: var(--muted);
  font-size: 14px;
}

.site-nav a {
  padding: 6px 0;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(360px, 1.08fr);
  gap: clamp(28px, 5vw, 72px);
  align-items: center;
  min-height: calc(100vh - 73px);
  padding: clamp(42px, 7vw, 92px) clamp(20px, 5vw, 72px) clamp(28px, 4vw, 48px);
}

.hero-copy {
  max-width: 660px;
}

.section-label {
  margin: 0 0 18px;
  color: var(--clay);
  font-size: 14px;
  font-weight: 700;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 22px;
  color: var(--ink);
  font-size: clamp(42px, 6.2vw, 76px);
  font-weight: 780;
  line-height: 1.06;
}

.hero-lede {
  max-width: 580px;
  margin-bottom: 0;
  color: var(--muted);
  font-size: clamp(17px, 1.7vw, 21px);
  line-height: 1.78;
}

.hero-visual {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.hero-visual img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.trust-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--surface);
}

.trust-strip article {
  min-height: 172px;
  padding: clamp(24px, 4vw, 38px);
  border-right: 1px solid var(--line);
}

.trust-strip article:last-child {
  border-right: 0;
}

.trust-strip h2,
.boundary-grid h3,
.method-item h3,
.privacy-principles h3 {
  margin-bottom: 10px;
  color: var(--ink-soft);
  font-size: 20px;
  line-height: 1.35;
}

.trust-strip p,
.boundary-grid p,
.method-item p,
.privacy-principles p,
.section-copy p,
.section-intro p {
  color: var(--muted);
  font-size: 16px;
  line-height: 1.78;
}

.section {
  padding: clamp(64px, 9vw, 112px) clamp(20px, 5vw, 72px);
}

.two-column,
.privacy-section {
  display: grid;
  grid-template-columns: minmax(260px, 0.85fr) minmax(0, 1.15fr);
  gap: clamp(28px, 6vw, 88px);
  align-items: start;
}

.section h2 {
  margin-bottom: 0;
  color: var(--ink);
  font-size: clamp(30px, 4vw, 52px);
  font-weight: 760;
  line-height: 1.16;
}

.section-copy p + p {
  margin-top: 18px;
}

.boundary-panel {
  border-block: 1px solid var(--line);
  background: var(--surface-muted);
}

.boundary-heading {
  display: grid;
  grid-template-columns: minmax(240px, 0.72fr) minmax(0, 1.28fr);
  gap: clamp(22px, 5vw, 72px);
  align-items: end;
  margin-bottom: clamp(28px, 5vw, 54px);
}

.boundary-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.boundary-grid article,
.privacy-principles article {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.78);
  padding: 24px;
}

.method-section {
  display: grid;
  grid-template-columns: minmax(280px, 0.82fr) minmax(0, 1.18fr);
  gap: clamp(30px, 6vw, 86px);
}

.section-intro {
  position: sticky;
  top: 112px;
  align-self: start;
}

.section-intro h2 {
  margin-bottom: 20px;
}

.method-list {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line-strong);
}

.method-item {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 24px;
  padding: 28px 0;
  border-bottom: 1px solid var(--line-strong);
}

.method-item span {
  color: var(--accent);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 22px;
}

.method-item p {
  margin-bottom: 0;
}

.privacy-section {
  background: var(--surface);
}

.privacy-principles {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 30px clamp(20px, 5vw, 72px);
  background: var(--graphite);
  color: #dfe8e2;
  font-size: 14px;
}

.site-footer p {
  margin-bottom: 8px;
  color: #bdc9c3;
  line-height: 1.7;
}

.footer-title {
  color: #ffffff;
  font-weight: 700;
}

.footer-divider {
  margin: 0 8px;
  color: #7f8c86;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 10px 18px;
  align-content: flex-start;
}

.footer-links a,
.site-footer a {
  text-decoration: underline;
  text-underline-offset: 4px;
}

@media (max-width: 940px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
  }

  .site-nav {
    justify-content: flex-start;
  }

  .hero,
  .two-column,
  .boundary-heading,
  .method-section,
  .privacy-section {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
  }

  .section-intro {
    position: static;
  }

  .trust-strip,
  .boundary-grid {
    grid-template-columns: 1fr;
  }

  .trust-strip article {
    min-height: auto;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .trust-strip article:last-child {
    border-bottom: 0;
  }
}

@media (max-width: 640px) {
  .site-header {
    padding: 16px 18px;
  }

  .site-nav {
    gap: 6px 16px;
    font-size: 13px;
  }

  .hero {
    padding: 34px 18px 24px;
  }

  h1 {
    font-size: 38px;
  }

  .section {
    padding: 56px 18px;
  }

  .privacy-principles {
    grid-template-columns: 1fr;
  }

  .method-item {
    grid-template-columns: 42px 1fr;
    gap: 16px;
  }

  .site-footer {
    flex-direction: column;
    padding: 28px 18px;
  }

  .footer-links {
    justify-content: flex-start;
  }
}