:root {
  color-scheme: light;
  --sg-bg: #f7f8fb;
  --sg-text: #172033;
  --sg-muted: #5d687d;
  --sg-line: #dce2ec;
  --sg-card: #ffffff;
  --sg-primary: #0d7a6f;
  --sg-primary-dark: #075b53;
  --sg-blue: #1b5fc1;
  --sg-gold: #a46711;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
  color: var(--sg-text);
  background: var(--sg-bg);
  line-height: 1.72;
}

a {
  color: inherit;
}

.seo-shell {
  min-height: 100vh;
}

.seo-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  max-width: 1120px;
  margin: 0 auto;
  padding: 22px 24px;
}

.seo-brand {
  display: inline-flex;
  flex-direction: column;
  text-decoration: none;
}

.seo-brand strong {
  font-size: 18px;
  letter-spacing: 0;
}

.seo-brand span {
  color: var(--sg-muted);
  font-size: 13px;
}

.seo-nav__links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 14px 20px;
  color: var(--sg-muted);
  font-size: 14px;
}

.seo-nav__links a {
  text-decoration: none;
}

.seo-nav__links a:hover {
  color: var(--sg-primary);
}

.seo-hero {
  border-top: 1px solid var(--sg-line);
  border-bottom: 1px solid var(--sg-line);
  background: #ffffff;
}

.seo-hero__inner,
.seo-section,
.seo-footer {
  max-width: 1120px;
  margin: 0 auto;
  padding: 56px 24px;
}

.seo-eyebrow {
  margin: 0 0 12px;
  color: var(--sg-primary);
  font-weight: 700;
  font-size: 14px;
}

.seo-hero h1 {
  max-width: 820px;
  margin: 0;
  font-size: clamp(34px, 5vw, 58px);
  line-height: 1.12;
  letter-spacing: 0;
}

.seo-lead {
  max-width: 820px;
  margin: 20px 0 0;
  color: var(--sg-muted);
  font-size: 18px;
}

.seo-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.seo-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 10px 18px;
  border: 1px solid var(--sg-primary);
  border-radius: 6px;
  color: var(--sg-primary-dark);
  text-decoration: none;
  font-weight: 700;
}

.seo-btn--primary {
  background: var(--sg-primary);
  color: #ffffff;
}

.seo-section h2 {
  margin: 0 0 18px;
  font-size: 28px;
  line-height: 1.25;
  letter-spacing: 0;
}

.seo-section > p {
  max-width: 820px;
  margin: 0 0 24px;
  color: var(--sg-muted);
}

.seo-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.seo-card {
  background: var(--sg-card);
  border: 1px solid var(--sg-line);
  border-radius: 8px;
  padding: 22px;
}

.seo-card h3 {
  margin: 0 0 10px;
  font-size: 19px;
  line-height: 1.35;
}

.seo-card p,
.seo-list li {
  color: var(--sg-muted);
}

.seo-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px 28px;
  margin: 0;
  padding-left: 20px;
}

.seo-note {
  border-left: 4px solid var(--sg-gold);
  background: #fff8ec;
  padding: 18px 20px;
  color: #5f421a;
}

.seo-footer {
  border-top: 1px solid var(--sg-line);
  color: var(--sg-muted);
  font-size: 14px;
}

@media (max-width: 760px) {
  .seo-nav {
    align-items: flex-start;
    flex-direction: column;
  }

  .seo-nav__links {
    justify-content: flex-start;
  }

  .seo-hero__inner,
  .seo-section,
  .seo-footer {
    padding: 42px 20px;
  }

  .seo-grid,
  .seo-list {
    grid-template-columns: 1fr;
  }
}