:root {
  --paper: #f7f3ec;
  --paper-elevated: #fcfaf6;
  --ink: #1a1712;
  --muted: #6b6253;
  --accent: #b84925;
  --accent-hover: #a6401e;
  --accent-soft: #f1e3dc;
  --line: #ded7c9;
  --line-strong: #c9bfae;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, "Times New Roman", serif;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-family: var(--sans);
  background: var(--paper);
  color: var(--ink);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 2rem;
  overflow-x: hidden;
}

body {
  margin: 0;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.28em;
}

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

a:focus-visible,
summary:focus-visible,
.table-wrap:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
  border-radius: 4px;
}

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

p {
  line-height: 1.72;
  color: var(--muted);
  margin-top: 0;
}

h1,
h2,
h3,
h4 {
  margin-top: 0;
  color: var(--ink);
  font-family: var(--serif);
  font-weight: 600;
}

h1 {
  font-size: clamp(2.45rem, 5.2vw, 4.4rem);
  line-height: 1.07;
  letter-spacing: -0.03em;
  margin-bottom: 1.35rem;
}

h2 {
  font-size: clamp(1.75rem, 3vw, 2.55rem);
  line-height: 1.18;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}

h3 {
  font-size: 1.25rem;
  line-height: 1.3;
  margin-bottom: 0.55rem;
}

h4 {
  font-size: 1.08rem;
  line-height: 1.35;
  margin-bottom: 0.45rem;
}

.site-header,
main,
.site-footer {
  width: min(1120px, calc(100% - 48px));
  margin-inline: auto;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding-block: 22px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-height: 44px;
  font-family: var(--serif);
  font-size: 1.28rem;
  font-weight: 600;
  text-decoration: none;
  letter-spacing: -0.02em;
}

.brand img {
  border-radius: 8px;
  border: 1px solid var(--line);
}

nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 20px;
  font-size: 0.94rem;
}

nav a {
  min-height: 44px;
  padding-inline: 4px;
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}

.lang-switch {
  padding-inline: 10px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  font-size: 0.86rem;
}

.skip {
  position: absolute;
  left: 24px;
  top: -120px;
  min-height: 44px;
  padding: 10px 18px;
  background: var(--ink);
  color: var(--paper);
  z-index: 10;
  text-decoration: none;
}

.skip:focus {
  top: 12px;
}

.project-status {
  font-size: 0.82rem;
  letter-spacing: 0.03em;
  color: var(--muted);
  border-top: 1px solid var(--line);
  padding-top: 18px;
  margin-bottom: 0;
}

.hero {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: start;
  padding-block: 56px 76px;
  border-bottom: 1px solid var(--line);
}

.hero-copy {
  max-width: 620px;
}

.eyebrow {
  color: var(--accent);
  font-family: var(--sans);
  font-size: 0.76rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 16px;
}

.lead {
  font-size: 1.12rem;
  max-width: 54ch;
  margin-bottom: 28px;
}

.hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 14px 24px;
}

.action {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  min-height: 48px;
  padding: 12px 22px;
  background: var(--accent);
  color: var(--paper-elevated);
  border-radius: 10px;
  text-decoration: none;
  font-weight: 600;
  font-size: 0.96rem;
}

.action:hover {
  color: var(--paper-elevated);
  background: var(--accent-hover);
}

.action-secondary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 48px;
  padding-inline: 6px;
  color: var(--ink);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.96rem;
}

.availability {
  font-size: 0.84rem;
  color: var(--muted);
  margin: 18px 0 0;
}

.hero-diagram {
  background: var(--paper-elevated);
  border: 1px solid var(--line-strong);
  border-radius: 14px;
  padding: 24px;
}

.diagram-header {
  border-bottom: 1px solid var(--line);
  padding-bottom: 14px;
  margin-bottom: 18px;
}

.diagram-badge {
  display: inline-block;
  font-size: 0.74rem;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 4px 10px;
  border-radius: 6px;
  margin-bottom: 10px;
}

.diagram-title {
  font-family: var(--serif);
  font-size: 1.12rem;
  font-weight: 600;
  color: var(--ink);
  margin: 0;
}

.diagram-flow {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 12px;
}

.diagram-node {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 14px 16px;
  background: var(--paper);
  display: grid;
  gap: 4px;
}

.diagram-node-accent {
  border-color: var(--accent);
  background: var(--paper-elevated);
}

.node-kicker {
  font-size: 0.74rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
}

.diagram-node strong {
  font-size: 0.98rem;
  color: var(--ink);
}

.diagram-node span:last-child {
  font-size: 0.85rem;
  color: var(--muted);
  line-height: 1.5;
}

.diagram-footnote {
  font-size: 0.78rem;
  line-height: 1.55;
  color: var(--muted);
  margin: 16px 0 0;
}

.section {
  padding-block: 72px;
  border-bottom: 1px solid var(--line);
}

.section-header {
  max-width: 680px;
  margin-bottom: 40px;
}

.section-lead {
  max-width: 60ch;
  font-size: 1.04rem;
  margin-bottom: 0;
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 36px;
  list-style: none;
  padding: 0;
  margin: 0;
}

.steps li {
  border-top: 1px solid var(--line-strong);
  padding-top: 20px;
}

.step-number {
  display: block;
  font-variant-numeric: tabular-nums;
  color: var(--accent);
  font-weight: 600;
  font-size: 0.86rem;
  margin-bottom: 14px;
}

.steps p {
  font-size: 0.95rem;
  margin-bottom: 0;
}

.split-section {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 56px;
  align-items: start;
}

.ledger-list {
  display: grid;
  gap: 24px;
}

.ledger-item {
  border-top: 1px solid var(--line);
  padding-top: 20px;
}

.ledger-item:first-child {
  border-top: 0;
  padding-top: 0;
}

.ledger-item p {
  font-size: 0.95rem;
  margin-bottom: 0;
}

.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--line-strong);
  border-radius: 12px;
  background: var(--paper-elevated);
  margin-bottom: 40px;
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.94rem;
}

.comparison-table th,
.comparison-table td {
  padding: 15px 18px;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

.comparison-table thead th {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.07em;
  color: var(--muted);
  background: var(--paper);
}

.comparison-table tbody tr:last-child th,
.comparison-table tbody tr:last-child td {
  border-bottom: 0;
}

.comparison-table tbody th {
  font-weight: 600;
  color: var(--ink);
}

.status-pill {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  padding: 3px 9px;
  border-radius: 6px;
  background: var(--paper);
  border: 1px solid var(--line-strong);
  color: var(--ink);
  white-space: nowrap;
}

.dev-preview {
  border: 1px solid var(--line-strong);
  border-left: 4px solid var(--accent);
  border-radius: 12px;
  padding: 28px;
  background: var(--paper-elevated);
}

.dev-badge {
  display: inline-block;
  font-size: 0.76rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 5px 11px;
  border-radius: 6px;
  margin-bottom: 14px;
}

.dev-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 24px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

.dev-item p {
  font-size: 0.92rem;
  margin-bottom: 0;
}

.faq {
  max-width: 860px;
  margin-inline: 0;
}

.faq-list {
  margin-top: 24px;
  border-top: 1px solid var(--line);
}

details {
  border-bottom: 1px solid var(--line);
}

summary {
  min-height: 48px;
  padding: 18px 0;
  font-size: 1.04rem;
  font-weight: 600;
  color: var(--ink);
  cursor: pointer;
}

details p {
  padding: 0 12px 18px 0;
  margin: 0;
  font-size: 0.96rem;
}

.doc-page {
  max-width: 760px;
}

.doc-meta {
  font-size: 0.88rem;
  color: var(--muted);
  margin-bottom: 20px;
}

.doc-sections {
  margin-block: 36px;
  display: grid;
  gap: 28px;
}

.doc-section {
  border-top: 1px solid var(--line);
  padding-top: 24px;
}

.doc-section h2 {
  font-size: 1.38rem;
  margin-bottom: 10px;
}

.doc-section p {
  margin-bottom: 0;
}

.contact {
  margin-block: 32px 24px;
  color: var(--ink);
  font-weight: 500;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 20px 32px;
  padding-block: 28px 40px;
  font-size: 0.88rem;
}

.footer-meta {
  display: grid;
  gap: 4px;
}

.brand-footer {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  font-family: var(--serif);
  font-weight: 600;
  font-size: 1.05rem;
  text-decoration: none;
}

.footer-meta p {
  margin: 0;
  font-size: 0.84rem;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
}

.footer-links a {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

@media (max-width: 767px) {
  .site-header,
  main,
  .site-footer {
    width: calc(100% - 32px);
  }

  .site-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    padding-block: 16px;
  }

  nav {
    gap: 4px 14px;
  }

  .hero,
  .steps,
  .split-section,
  .dev-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .hero {
    padding-block: 36px 52px;
  }

  .section {
    padding-block: 52px;
  }

  .dev-preview {
    padding: 20px;
  }

  .comparison-table th,
  .comparison-table td {
    padding: 12px;
    font-size: 0.88rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition: none !important;
    animation: none !important;
  }
}