:root {
  --page: #f5efe7;
  --surface: rgba(255, 255, 255, 0.82);
  --surface-strong: rgba(255, 255, 255, 0.94);
  --surface-dark: #111823;
  --surface-dark-2: #182534;
  --ink: #17212a;
  --ink-soft: #54626e;
  --line: rgba(23, 33, 42, 0.12);
  --accent: #c36b41;
  --accent-strong: #a54e27;
  --mint: #2c7366;
  --mint-soft: rgba(44, 115, 102, 0.12);
  --gold: #d1a451;
  --max: 1180px;
  --radius-xl: 32px;
  --radius-lg: 24px;
  --radius-md: 18px;
  --radius-sm: 12px;
  --shadow-lg: 0 28px 80px rgba(17, 24, 35, 0.12);
  --shadow-md: 0 18px 36px rgba(17, 24, 35, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at top right, rgba(195, 107, 65, 0.16), transparent 24rem),
    radial-gradient(circle at 0% 18%, rgba(44, 115, 102, 0.12), transparent 28rem),
    linear-gradient(180deg, #faf5ec 0%, var(--page) 42%, #f1e8db 100%);
  color: var(--ink);
  font-family: "Aptos", "Segoe UI Variable Text", "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.65;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(17, 24, 35, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(17, 24, 35, 0.025) 1px, transparent 1px);
  background-size: 40px 40px;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.22), transparent 70%);
}

a {
  color: inherit;
}

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

code {
  padding: 0.12rem 0.38rem;
  border-radius: 999px;
  background: rgba(23, 33, 42, 0.06);
  font-family: "Consolas", "SFMono-Regular", monospace;
  font-size: 0.92em;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: 1rem;
  transform: translateY(-180%);
  padding: 0.7rem 1rem;
  border-radius: 999px;
  background: var(--surface-dark);
  color: #fff;
  z-index: 100;
}

.skip-link:focus {
  transform: translateY(0);
}

.container {
  width: min(var(--max), calc(100vw - 2rem));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  backdrop-filter: blur(18px);
  background: rgba(250, 245, 236, 0.82);
  border-bottom: 1px solid rgba(23, 33, 42, 0.08);
}

.site-header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 5rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.9rem;
  text-decoration: none;
}

.brand img {
  width: 2.8rem;
  height: 2.8rem;
  border-radius: 1rem;
  box-shadow: var(--shadow-md);
}

.brand-copy {
  display: grid;
  gap: 0.12rem;
}

.brand-copy strong {
  font-size: 1rem;
}

.brand-copy span {
  color: var(--ink-soft);
  font-size: 0.76rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 2.8rem;
  height: 2.8rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.72);
  color: var(--ink);
  cursor: pointer;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.nav-links a {
  text-decoration: none;
  padding: 0.6rem 0.9rem;
  border-radius: 999px;
  color: var(--ink-soft);
  font-size: 0.94rem;
  white-space: nowrap;
  transition: background-color 180ms ease, color 180ms ease, transform 180ms ease;
}

.nav-links a:hover,
.nav-links a:focus-visible,
.nav-links a.is-active {
  color: var(--ink);
  background: rgba(23, 33, 42, 0.06);
  transform: translateY(-1px);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.5rem 0.8rem;
  border-radius: 999px;
  background: rgba(195, 107, 65, 0.12);
  color: var(--accent-strong);
  font-size: 0.84rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.eyebrow.mint {
  color: var(--mint);
  background: var(--mint-soft);
}

h1,
h2,
h3,
h4 {
  margin: 0;
  line-height: 1.08;
  letter-spacing: -0.02em;
  font-family: "Iowan Old Style", "Palatino Linotype", "Source Han Serif SC", "Songti SC", serif;
}

p {
  margin: 0;
}

.section {
  padding: 4.4rem 0 1rem;
}

.section-head {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(18rem, 0.9fr);
  gap: 1rem;
  align-items: end;
  margin-bottom: 1.4rem;
}

.section-head h2 {
  font-size: clamp(2rem, 3.5vw, 3.5rem);
}

.section-head p {
  color: var(--ink-soft);
}

.hero,
.page-hero {
  padding: 2rem 0 1rem;
}

.hero-panel,
.page-hero-panel,
.cta-panel {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
}

.hero-panel {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(290px, 0.85fr);
  gap: 1.2rem;
  padding: 2rem;
  background:
    radial-gradient(circle at 80% 12%, rgba(209, 164, 81, 0.2), transparent 18rem),
    radial-gradient(circle at 12% 18%, rgba(44, 115, 102, 0.18), transparent 22rem),
    linear-gradient(135deg, var(--surface-dark) 0%, var(--surface-dark-2) 100%);
  color: #f8f3ea;
}

.hero-panel::after,
.page-hero-panel::after,
.cta-panel::after {
  content: "";
  position: absolute;
  inset: auto -4rem -4rem auto;
  width: 16rem;
  height: 16rem;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(195, 107, 65, 0.24), transparent 68%);
}

.hero-copy {
  display: grid;
  gap: 1.2rem;
  align-content: start;
}

.hero-copy h1 {
  font-size: clamp(3rem, 5vw, 5.8rem);
  max-width: 10.5ch;
}

.hero-copy .lead,
.page-hero-panel p {
  color: rgba(248, 243, 234, 0.8);
}

.hero-actions,
.button-row,
.hero-pills,
.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-height: 3.1rem;
  padding: 0.85rem 1.15rem;
  border-radius: 999px;
  border: 1px solid transparent;
  font-weight: 700;
  text-decoration: none;
  transition: transform 180ms ease, box-shadow 180ms ease, background-color 180ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-2px);
}

.button.primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  color: #fff8f2;
  box-shadow: 0 14px 30px rgba(195, 107, 65, 0.26);
}

.button.secondary {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.16);
  color: #fff8f2;
}

.button.light {
  background: rgba(255, 255, 255, 0.92);
  border-color: rgba(23, 33, 42, 0.08);
  color: var(--ink);
}

.button.ghost {
  background: transparent;
  border-color: rgba(23, 33, 42, 0.12);
  color: var(--ink);
}

.pill {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.42rem 0.72rem;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
  color: rgba(248, 243, 234, 0.86);
  border: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 0.84rem;
}

.hero-side,
.article-stack,
.toc-stack,
.timeline {
  display: grid;
  gap: 1rem;
}

.metric-grid,
.grid-2,
.grid-3,
.grid-4,
.split-grid,
.flow-grid,
.page-grid,
.site-footer-inner {
  display: grid;
  gap: 1rem;
}

.metric-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.metric-card {
  padding: 1.05rem;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: #fff8f2;
}

.metric-card strong {
  display: block;
  font-size: 1.05rem;
  margin-bottom: 0.25rem;
}

.metric-card span {
  color: rgba(248, 243, 234, 0.72);
  font-size: 0.92rem;
}

.metric-note,
.note-strip {
  padding: 1rem 1.05rem;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.1);
  color: rgba(248, 243, 234, 0.84);
}

.surface-card,
.grid-card,
.timeline-card,
.split-card,
.toc-card,
.article-card,
.cta-panel {
  background: var(--surface-strong);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-md);
  border-radius: var(--radius-lg);
  padding: 1.2rem;
}

.grid-2,
.split-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3,
.flow-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.flow-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.page-grid {
  grid-template-columns: minmax(0, 1fr) minmax(260px, 0.34fr);
}

.site-footer-inner {
  grid-template-columns: minmax(0, 1fr) minmax(260px, 0.8fr);
}

.grid-card h3,
.split-card h3,
.timeline-card h3,
.article-card h3,
.toc-card h3 {
  font-size: 1.3rem;
  margin-bottom: 0.55rem;
}

.grid-card p,
.split-card p,
.timeline-card p,
.article-card p,
.article-card li,
.toc-card li,
.site-footer p,
.site-footer li,
.section p,
.section li {
  color: var(--ink-soft);
}

.grid-card ul,
.split-card ul,
.timeline-card ul,
.article-card ul,
.toc-card ul {
  margin: 0.8rem 0 0;
  padding-left: 1.1rem;
}

.grid-card li,
.split-card li,
.timeline-card li,
.article-card li,
.toc-card li {
  margin-bottom: 0.42rem;
}

.split-card.highlight {
  background:
    radial-gradient(circle at top right, rgba(209, 164, 81, 0.18), transparent 13rem),
    var(--surface-strong);
}

.flow-card {
  position: relative;
  padding: 1.1rem;
  border-radius: var(--radius-lg);
  border: 1px dashed rgba(23, 33, 42, 0.14);
  background: rgba(255, 255, 255, 0.62);
}

.flow-card span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  margin-bottom: 0.8rem;
  border-radius: 999px;
  background: var(--mint-soft);
  color: var(--mint);
  font-weight: 700;
}

.flow-inline,
.note-strip {
  margin-top: 1rem;
  padding: 1rem 1.2rem;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, rgba(17, 24, 35, 0.96), rgba(24, 37, 52, 0.96));
  color: #f8f3ea;
}

.note-strip p,
.note-strip li {
  color: rgba(248, 243, 234, 0.8);
}

.cta-panel {
  background:
    radial-gradient(circle at top right, rgba(209, 164, 81, 0.16), transparent 12rem),
    linear-gradient(135deg, rgba(255, 255, 255, 0.92), rgba(255, 255, 255, 0.82));
}

.flow-inline {
  overflow-x: auto;
  white-space: nowrap;
  font-family: "Consolas", "SFMono-Regular", monospace;
}

.page-hero-panel {
  padding: 1.8rem;
  background:
    radial-gradient(circle at top right, rgba(195, 107, 65, 0.18), transparent 16rem),
    linear-gradient(135deg, rgba(17, 24, 35, 0.98), rgba(24, 37, 52, 0.98));
  color: #f8f3ea;
}

.page-hero-panel h1 {
  font-size: clamp(2.6rem, 4.4vw, 4.8rem);
  max-width: 11ch;
  margin: 1rem 0;
}

.toc-card {
  position: sticky;
  top: 6.2rem;
}

.toc-card ul {
  list-style: none;
  padding: 0;
}

.toc-card li {
  margin-bottom: 0.2rem;
}

.toc-card a {
  display: block;
  padding: 0.45rem 0.6rem;
  border-radius: 0.75rem;
  text-decoration: none;
}

.toc-card a:hover,
.toc-card a:focus-visible {
  background: rgba(23, 33, 42, 0.05);
  color: var(--ink);
}

.timeline-card header {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.7rem;
  margin-bottom: 0.65rem;
}

.timeline-card time {
  color: var(--accent-strong);
  font-size: 0.84rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.cta-panel h2 {
  font-size: clamp(1.8rem, 3vw, 2.8rem);
  margin-bottom: 0.7rem;
}

.site-footer {
  padding: 4rem 0 3rem;
}

.site-footer-inner {
  padding-top: 1.4rem;
  border-top: 1px solid rgba(23, 33, 42, 0.08);
}

.footer-links a {
  text-decoration: none;
  padding: 0.45rem 0.7rem;
  border-radius: 999px;
  background: rgba(23, 33, 42, 0.05);
}

.footer-links a:hover,
.footer-links a:focus-visible {
  background: rgba(23, 33, 42, 0.1);
}

.site-footer ul {
  padding-left: 1.1rem;
}

.site-footer li {
  margin-bottom: 0.3rem;
}

@media (max-width: 1100px) {
  .hero-panel,
  .section-head,
  .page-grid,
  .site-footer-inner {
    grid-template-columns: 1fr;
  }

  .grid-4,
  .flow-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 820px) {
  .nav-toggle {
    display: inline-flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: calc(100% + 0.5rem);
    right: 1rem;
    left: 1rem;
    flex-direction: column;
    align-items: stretch;
    gap: 0.25rem;
    padding: 0.75rem;
    border-radius: var(--radius-lg);
    background: rgba(255, 255, 255, 0.95);
    border: 1px solid rgba(23, 33, 42, 0.08);
    box-shadow: var(--shadow-lg);
  }

  .nav-links[data-open="true"] {
    display: flex;
  }

  .metric-grid,
  .grid-2,
  .grid-3,
  .grid-4,
  .split-grid,
  .flow-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .site-header-inner {
    min-height: 4.5rem;
  }

  .hero-panel,
  .page-hero-panel,
  .grid-card,
  .timeline-card,
  .split-card,
  .toc-card,
  .article-card,
  .cta-panel {
    padding: 1.1rem;
  }

  .section {
    padding-top: 3.5rem;
  }

  .hero-copy h1,
  .page-hero-panel h1 {
    max-width: none;
    font-size: clamp(2.2rem, 12vw, 3.3rem);
  }

  .button,
  .button.light,
  .button.ghost {
    width: 100%;
  }
}