:root {
  --sub-bg: #f4eedf;
  --sub-paper: #fbf7ec;
  --sub-ink: #1e1812;
  --sub-muted: rgba(30, 24, 18, 0.66);
  --sub-line: rgba(30, 24, 18, 0.14);
  --sub-accent: #9b4419;
  --sub-accent-display: #c25d2c;
  --sub-soft: #f2d9c6;
  --sub-display: Georgia, "Songti SC", "STSong", serif;
  --sub-ui: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

html { scroll-padding-top: 92px; }

body {
  min-width: 320px;
  background: var(--sub-bg);
  color: var(--sub-ink);
  font-family: var(--sub-ui);
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(circle at 78% 9%, rgba(194, 93, 44, 0.08), transparent 25rem),
    repeating-linear-gradient(0deg, transparent 0 31px, rgba(30, 24, 18, 0.018) 31px 32px);
}

a { color: inherit; }

.site-header {
  position: sticky;
  inset: 0 0 auto;
  z-index: 20;
  display: grid;
  grid-template-columns: minmax(120px, 1fr) auto minmax(160px, 1fr);
  align-items: center;
  gap: 28px;
  min-height: 74px;
  padding: 0 max(20px, calc((100vw - 1180px) / 2));
  background: color-mix(in srgb, var(--sub-paper) 94%, transparent);
  color: var(--sub-ink);
  border-bottom: 1px solid var(--sub-line);
  backdrop-filter: blur(18px);
}

.site-header.is-scrolled {
  padding-top: 0;
  padding-bottom: 0;
  background: color-mix(in srgb, var(--sub-paper) 94%, transparent);
  color: var(--sub-ink);
  border-color: var(--sub-line);
}

.brand { display: inline-flex; width: fit-content; align-items: center; }
.brand-logo { width: auto; height: 24px; object-fit: contain; filter: invert(1); }

.nav { display: flex; align-items: center; justify-content: center; gap: 20px; }
.nav a {
  position: relative;
  color: var(--sub-ink);
  font-size: 13px;
  font-weight: 500;
  text-decoration: none;
}
.nav a::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: -9px;
  left: 0;
  height: 1px;
  background: var(--sub-accent);
  transform: scaleX(0);
  transition: transform 160ms ease;
}
.nav a:hover::after,
.nav a:focus-visible::after { transform: scaleX(1); }

.header-actions { display: flex; justify-content: flex-end; }
.header-cta,
.btn-primary {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  padding: 0 18px;
  border: 0;
  border-radius: 999px;
  background: var(--sub-accent);
  color: #fff9ed;
  font-size: 13px;
  font-weight: 650;
  text-decoration: none;
  box-shadow: none;
}

.seo-page {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
  padding: 0 0 88px;
}

.seo-hero {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.45fr) minmax(280px, 0.55fr);
  gap: 56px;
  align-items: end;
  padding: 84px 0 54px;
  border-bottom: 1px solid var(--sub-line);
}
.seo-hero::before {
  content: "Golang / West Bund";
  position: absolute;
  top: 38px;
  left: 0;
  color: var(--sub-accent);
  font: italic 20px/1 var(--sub-display);
  transform: rotate(-2deg);
}
.seo-hero::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: -1px;
  width: min(34vw, 360px);
  height: 3px;
  background: var(--sub-accent-display);
}
.seo-hero h1 {
  max-width: 780px;
  margin: 0;
  font: italic 400 clamp(48px, 6.3vw, 84px) / 1.02 var(--sub-display);
  letter-spacing: -0.035em;
  text-wrap: balance;
}
.seo-hero p {
  max-width: 440px;
  margin: 0;
  color: var(--sub-muted);
  font-size: 15px;
  line-height: 1.8;
  text-wrap: pretty;
}

.seo-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.5fr) minmax(280px, 0.5fr);
  gap: 22px;
  align-items: start;
  padding-top: 38px;
}
.seo-panel {
  padding: 30px;
  background: var(--sub-paper);
  color: var(--sub-ink);
  border: 1px solid var(--sub-line);
  border-radius: 12px;
  box-shadow: none;
}
.seo-panel:first-child { padding: clamp(30px, 4vw, 48px); }
.seo-panel h2 {
  margin: 0 0 18px;
  font: italic 400 clamp(26px, 3vw, 38px) / 1.12 var(--sub-display);
  letter-spacing: -0.02em;
}
.seo-panel h3 {
  margin: 28px 0 10px;
  font: italic 400 22px/1.25 var(--sub-display);
}
.seo-panel p,
.seo-list {
  color: var(--sub-muted);
  font-size: 15px;
  line-height: 1.85;
}
.seo-panel p { max-width: 72ch; }
.seo-panel a:not(.btn) {
  color: var(--sub-accent);
  text-decoration-color: color-mix(in srgb, var(--sub-accent) 40%, transparent);
  text-underline-offset: 4px;
}
.seo-list { margin: 24px 0 0; padding: 0; list-style: none; }
.seo-list li { position: relative; padding: 13px 0 13px 22px; border-top: 1px solid var(--sub-line); }
.seo-list li::before { content: ""; position: absolute; top: 22px; left: 2px; width: 7px; height: 7px; border-radius: 50%; background: var(--sub-accent-display); }
.seo-panel .btn { margin-top: 10px; }

:focus-visible { outline: 3px solid var(--sub-accent-display); outline-offset: 3px; }

@media (max-width: 820px) {
  html { scroll-padding-top: 118px; }
  .site-header {
    grid-template-columns: 1fr auto;
    gap: 8px 14px;
    padding: 12px 16px 10px;
  }
  .brand-logo { height: 20px; }
  .header-cta { padding: 0 14px; }
  .nav {
    grid-column: 1 / -1;
    grid-row: 2;
    justify-content: flex-start;
    gap: 20px;
    padding: 10px 0 2px;
    overflow-x: auto;
    border-top: 1px solid var(--sub-line);
    scrollbar-width: none;
  }
  .nav::-webkit-scrollbar { display: none; }
  .nav a { flex: 0 0 auto; white-space: nowrap; }
  .seo-page { width: min(100% - 32px, 720px); padding-bottom: 56px; }
  .seo-hero { grid-template-columns: 1fr; gap: 24px; padding: 78px 0 36px; }
  .seo-hero::before { top: 34px; }
  .seo-hero h1 { font-size: clamp(42px, 12.5vw, 62px); }
  .seo-hero::after { width: 46%; }
  .seo-layout { grid-template-columns: 1fr; padding-top: 22px; }
  .seo-panel,
  .seo-panel:first-child { padding: 24px; }
}

@media (prefers-color-scheme: dark) {
  :root {
    --sub-bg: #17120d;
    --sub-paper: #201a14;
    --sub-ink: #f4eedf;
    --sub-muted: rgba(244, 238, 223, 0.64);
    --sub-line: rgba(244, 238, 223, 0.16);
    --sub-accent: #e8905c;
    --sub-accent-display: #e8905c;
    --sub-soft: #3a2a1f;
  }
  .brand-logo { filter: none; }
  .header-cta,
  .btn-primary { color: #17120d; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; }
}