:root {
  --bg: #f4f8f8;
  --bg-soft: #edf3f4;
  --bg-deep: #e7eef0;
  --paper: rgba(255, 255, 255, 0.76);
  --paper-strong: rgba(255, 255, 255, 0.92);
  --paper-muted: rgba(248, 251, 251, 0.72);
  --line: rgba(15, 37, 47, 0.09);
  --line-strong: rgba(15, 37, 47, 0.14);
  --text: #0f212a;
  --muted: #52636e;
  --muted-strong: #324550;
  --accent: #2d6f73;
  --accent-strong: #1f5458;
  --accent-soft: rgba(45, 111, 115, 0.1);
  --accent-softer: rgba(45, 111, 115, 0.05);
  --accent-glow: rgba(98, 177, 179, 0.24);
  --shadow-xl: 0 34px 90px rgba(16, 38, 48, 0.08);
  --shadow-lg: 0 20px 48px rgba(16, 38, 48, 0.08);
  --shadow-md: 0 10px 28px rgba(16, 38, 48, 0.06);
  --radius-2xl: 34px;
  --radius-xl: 28px;
  --radius-lg: 22px;
  --radius-md: 18px;
  --radius-sm: 14px;
  --font-sans: "SF Pro Display", "PingFang SC", "Noto Sans SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-serif: "Iowan Old Style", "Songti SC", "Noto Serif SC", serif;
  --font-mono: "SFMono-Regular", "JetBrains Mono", "Menlo", "Monaco", monospace;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  background:
    radial-gradient(circle at 12% 16%, rgba(91, 174, 177, 0.22), transparent 24rem),
    radial-gradient(circle at 88% 0%, rgba(255, 255, 255, 0.9), transparent 28rem),
    linear-gradient(180deg, #f7fbfb 0%, #eef4f5 46%, #f4f7f7 100%);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(rgba(255, 255, 255, 0.28), rgba(255, 255, 255, 0.28)),
    linear-gradient(90deg, transparent 0, transparent calc(100% - 1px), rgba(15, 37, 47, 0.025) calc(100% - 1px)),
    linear-gradient(transparent 0, transparent calc(100% - 1px), rgba(15, 37, 47, 0.02) calc(100% - 1px));
  background-size: auto, 96px 96px, 96px 96px;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.14), transparent 78%);
}

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

.home-shell {
  width: min(1280px, calc(100% - 40px));
  margin: 0 auto;
  padding: 24px 0 56px;
  position: relative;
}

.doc-shell {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 300px minmax(0, 1fr);
}

.masthead {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 18px;
}

.masthead-actions,
.header-actions,
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.site-mark {
  display: inline-flex;
  flex-direction: column;
  gap: 4px;
}

.site-mark-kicker,
.eyebrow,
.sheet-kicker,
.guide-kicker,
.card-tag,
.path-index,
.metric-card span,
.timeline-card span {
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-size: 0.74rem;
  color: var(--accent);
}

.site-mark strong {
  font-family: var(--font-serif);
  font-size: 1.6rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.site-mark-copy {
  margin: 0 0 28px;
  color: var(--muted);
  line-height: 1.75;
  font-size: 0.95rem;
}

.ghost-button,
.primary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 18px;
  border-radius: 999px;
  font-size: 0.95rem;
  font-weight: 600;
  border: 1px solid var(--line-strong);
  background: rgba(255, 255, 255, 0.56);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.72);
  transition:
    transform 160ms ease,
    border-color 160ms ease,
    background 160ms ease,
    box-shadow 160ms ease;
}

.primary-button {
  color: #f3fbfb;
  border-color: rgba(31, 84, 88, 0.46);
  background: linear-gradient(135deg, var(--accent-strong), var(--accent));
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.22),
    0 14px 30px rgba(31, 84, 88, 0.18);
}

.ghost-button:hover,
.primary-button:hover,
.path-step:hover,
.feature-card:hover,
.download-card:hover,
.doc-nav-link:hover,
.guide-link:hover {
  transform: translateY(-2px);
}

.ghost-button:hover,
.doc-nav-link:hover,
.guide-link:hover {
  border-color: rgba(31, 84, 88, 0.22);
  background: rgba(255, 255, 255, 0.78);
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.18fr) minmax(320px, 0.82fr);
  gap: 18px;
  margin-bottom: 18px;
}

.hero-main,
.hero-sheet,
.metric-card,
.signal-panel,
.feature-card,
.timeline-card,
.download-card,
.article-card,
.guide-card,
.doc-sidebar {
  border: 1px solid var(--line);
  background: var(--paper);
  backdrop-filter: blur(18px);
  box-shadow: var(--shadow-lg);
}

.hero-main,
.hero-sheet,
.signal-panel,
.article-card,
.guide-card {
  position: relative;
  overflow: hidden;
}

.hero-main {
  padding: clamp(32px, 5vw, 56px);
  border-radius: var(--radius-2xl);
  background:
    radial-gradient(circle at top right, rgba(103, 191, 194, 0.14), transparent 20rem),
    linear-gradient(160deg, rgba(255, 255, 255, 0.86), rgba(247, 251, 252, 0.78));
}

.hero-main::after {
  content: "";
  position: absolute;
  right: -110px;
  top: -110px;
  width: 260px;
  height: 260px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-glow), transparent 68%);
  pointer-events: none;
}

.hero-main h1 {
  max-width: 15ch;
  margin: 10px 0 14px;
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4.4vw, 3.2rem);
  line-height: 1.12;
  letter-spacing: -0.035em;
}

.hero-main p {
  max-width: 44rem;
  margin: 0;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.82;
}

.hero-sheet {
  padding: 28px;
  border-radius: var(--radius-xl);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.88), rgba(244, 249, 249, 0.82));
}

.path-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 16px;
}

.path-step {
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 16px;
  border-radius: var(--radius-md);
  border: 1px solid var(--line);
  background: var(--paper-muted);
  transition:
    transform 160ms ease,
    border-color 160ms ease,
    background 160ms ease,
    box-shadow 160ms ease;
}

.path-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  border: 1px solid rgba(45, 111, 115, 0.18);
  background: rgba(255, 255, 255, 0.85);
  font-family: var(--font-mono);
  letter-spacing: 0.14em;
}

.path-step strong {
  display: block;
  margin: 2px 0 8px;
  font-size: 1.03rem;
}

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

.path-action,
.card-action,
.doc-nav-cta {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--accent-strong);
  font-size: 0.92rem;
  font-weight: 600;
}

.path-action::after,
.card-action::after,
.doc-nav-cta::after {
  content: "→";
  font-size: 0.95em;
}

.path-action {
  margin-top: 12px;
}

.section {
  margin-top: 22px;
}

.section-heading {
  max-width: 56rem;
  margin-bottom: 18px;
}

.section-heading h2,
.signal-head h2 {
  margin: 8px 0 12px;
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  line-height: 1.16;
  letter-spacing: -0.03em;
}

.section-heading p,
.signal-head p {
  margin: 0;
  color: var(--muted);
  line-height: 1.82;
}

.metric-grid,
.feature-grid,
.timeline-grid,
.download-grid {
  display: grid;
  gap: 16px;
}

.metric-grid {
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.feature-grid {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.timeline-grid {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.download-grid {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.metric-card,
.feature-card,
.timeline-card,
.download-card {
  min-height: 100%;
  border-radius: var(--radius-lg);
  padding: 20px;
  transition:
    transform 160ms ease,
    border-color 160ms ease,
    box-shadow 160ms ease,
    background 160ms ease;
}

.metric-card {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.84), rgba(245, 249, 250, 0.74));
}

.metric-card strong {
  display: block;
  margin: 12px 0 10px;
  font-size: 1.24rem;
  line-height: 1.35;
  letter-spacing: -0.02em;
}

.metric-card p,
.feature-card p,
.timeline-card p,
.download-card p {
  margin: 0;
  color: var(--muted);
  line-height: 1.76;
}

.signal-panel {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(0, 1.08fr);
  gap: 24px;
  padding: 28px;
  border-radius: var(--radius-xl);
  background:
    radial-gradient(circle at top right, rgba(103, 191, 194, 0.14), transparent 18rem),
    linear-gradient(150deg, rgba(255, 255, 255, 0.88), rgba(242, 248, 249, 0.78));
}

.signal-chart {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 18px;
}

.signal-row {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(140px, 1fr) auto;
  gap: 14px;
  align-items: center;
}

.signal-row span {
  color: var(--muted-strong);
  font-weight: 500;
}

.signal-row strong {
  font-size: 0.95rem;
  color: var(--accent-strong);
}

.signal-track {
  height: 10px;
  border-radius: 999px;
  background: rgba(15, 37, 47, 0.08);
  overflow: hidden;
}

.signal-track i {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, #75c0c1, var(--accent));
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.4);
}

.feature-card {
  display: flex;
  flex-direction: column;
  gap: 0;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.84), rgba(244, 249, 249, 0.76));
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 10px;
}

.card-index,
.doc-nav-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 34px;
  height: 28px;
  padding: 0 8px;
  border-radius: 999px;
  border: 1px solid rgba(45, 111, 115, 0.18);
  background: rgba(255, 255, 255, 0.88);
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: var(--accent-strong);
}

.feature-card h3 {
  margin: 12px 0 10px;
  font-size: 1.18rem;
  line-height: 1.36;
  letter-spacing: -0.02em;
}

.card-action {
  margin-top: auto;
  padding-top: 16px;
}

.timeline-card {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.88), rgba(246, 250, 250, 0.8));
}

.timeline-card strong {
  display: block;
  margin: 12px 0 10px;
  font-size: 1.08rem;
}

.download-card {
  display: flex;
  flex-direction: column;
  gap: 12px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.9), rgba(244, 249, 249, 0.82));
}

.download-card strong {
  font-size: 1.16rem;
  line-height: 1.35;
}

.download-card span {
  margin-top: auto;
  padding-top: 8px;
  color: var(--accent-strong);
  font-size: 0.92rem;
  font-weight: 600;
}

.doc-sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  padding: 28px 20px;
  overflow: auto;
  border-radius: 0;
  border-left: 0;
  border-top: 0;
  border-bottom: 0;
  background:
    linear-gradient(180deg, rgba(249, 252, 252, 0.94), rgba(239, 245, 246, 0.86));
  box-shadow:
    inset -1px 0 0 rgba(15, 37, 47, 0.06),
    0 0 0 transparent;
}

.doc-nav {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.doc-nav-link {
  display: flex;
  flex-direction: column;
  padding: 13px 14px;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  background: rgba(255, 255, 255, 0.42);
  transition:
    transform 160ms ease,
    border-color 160ms ease,
    background 160ms ease,
    box-shadow 160ms ease;
}

.doc-nav-topline {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-size: 0.68rem;
  color: var(--accent);
}

.doc-nav-link strong {
  display: block;
  font-size: 0.99rem;
  line-height: 1.5;
}

.doc-nav-link small {
  display: block;
  margin-top: 8px;
  color: var(--muted);
  line-height: 1.56;
}

.doc-nav-cta {
  margin-top: 10px;
}

.doc-nav-link.active {
  border-color: rgba(45, 111, 115, 0.18);
  background: linear-gradient(180deg, rgba(45, 111, 115, 0.1), rgba(45, 111, 115, 0.06));
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.62);
}

.mobile-doc-directory {
  display: none;
  width: min(1380px, 100%);
  margin: 0 auto 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.92), rgba(245, 250, 250, 0.84));
  box-shadow: var(--shadow-md);
  overflow: hidden;
}

.mobile-doc-directory summary {
  list-style: none;
  cursor: pointer;
  padding: 16px 18px;
  font-size: 0.98rem;
  font-weight: 600;
  color: var(--muted-strong);
}

.mobile-doc-directory summary::-webkit-details-marker {
  display: none;
}

.mobile-doc-directory summary::after {
  content: "展开";
  float: right;
  color: var(--accent-strong);
  font-size: 0.88rem;
  font-weight: 600;
}

.mobile-doc-directory[open] summary::after {
  content: "收起";
}

.mobile-doc-nav {
  padding: 0 14px 14px;
}

.doc-main {
  padding: 30px clamp(18px, 4vw, 42px) 56px;
}

.doc-header,
.doc-layout {
  width: min(1380px, 100%);
  margin: 0 auto;
}

.doc-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 22px;
}

.doc-header h1 {
  margin: 12px 0 12px;
  font-family: var(--font-serif);
  font-size: clamp(2rem, 3.6vw, 3.3rem);
  line-height: 1.08;
  letter-spacing: -0.04em;
}

.doc-header p {
  max-width: 42rem;
  margin: 0;
  color: var(--muted);
  line-height: 1.82;
}

.doc-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 286px;
  gap: 22px;
  align-items: start;
}

.article-card,
.guide-card {
  border-radius: var(--radius-xl);
}

.article-card {
  padding: clamp(24px, 3vw, 34px);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.94), rgba(248, 251, 251, 0.86));
}

.guide-card {
  position: sticky;
  top: 24px;
  padding: 22px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.9), rgba(244, 249, 249, 0.82));
}

.guide-block + .guide-block {
  margin-top: 22px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

.toc-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 14px;
}

.toc-item,
.toc-subitem {
  color: var(--muted);
  line-height: 1.5;
  transition: color 140ms ease;
}

.toc-item:hover,
.toc-subitem:hover {
  color: var(--accent-strong);
}

.toc-subitem {
  padding-left: 12px;
  font-size: 0.95rem;
}

.guide-link {
  display: block;
  margin-top: 12px;
  padding: 13px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.52);
  color: var(--muted-strong);
  transition:
    transform 160ms ease,
    border-color 160ms ease,
    background 160ms ease;
}

.muted {
  color: var(--muted);
}

.prose {
  font-size: 1rem;
  line-height: 1.92;
}

.prose h1,
.prose h2,
.prose h3 {
  scroll-margin-top: 24px;
}

.prose h1 {
  margin: 0 0 22px;
  font-family: var(--font-serif);
  font-size: 2rem;
  line-height: 1.08;
}

.prose h2 {
  margin: 42px 0 14px;
  padding-top: 10px;
  border-top: 1px solid rgba(15, 37, 47, 0.08);
  font-family: var(--font-serif);
  font-size: 1.62rem;
  line-height: 1.22;
}

.prose h3 {
  margin: 28px 0 10px;
  font-size: 1.14rem;
  line-height: 1.55;
}

.prose p,
.prose ul,
.prose ol,
.prose pre,
.prose .table-wrap {
  margin: 0 0 18px;
}

.prose ul,
.prose ol {
  padding-left: 22px;
}

.prose li {
  margin-bottom: 8px;
}

.prose strong {
  color: var(--muted-strong);
}

.prose code {
  padding: 0.18em 0.46em;
  border-radius: 9px;
  background: rgba(15, 37, 47, 0.06);
  font-family: var(--font-mono);
  font-size: 0.92em;
}

.prose pre {
  padding: 18px 20px;
  overflow-x: auto;
  border-radius: var(--radius-md);
  background: #10202a;
  color: #eaf4f5;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.05);
}

.prose pre code {
  padding: 0;
  background: transparent;
  color: inherit;
}

.table-wrap {
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.prose table {
  width: max-content;
  min-width: 100%;
  border-collapse: collapse;
  border-radius: var(--radius-md);
}

.prose th,
.prose td {
  padding: 12px 14px;
  border: 1px solid rgba(15, 37, 47, 0.08);
  vertical-align: top;
  text-align: left;
  word-break: break-word;
  overflow-wrap: anywhere;
}

.prose th {
  background: rgba(45, 111, 115, 0.08);
}

.prose tr:nth-child(even) td {
  background: rgba(244, 249, 249, 0.7);
}

.prose a {
  color: var(--accent-strong);
  text-decoration: underline;
  text-decoration-color: rgba(31, 84, 88, 0.22);
  text-underline-offset: 0.18em;
}

.prose p,
.prose li {
  overflow-wrap: anywhere;
}

.hero-main,
.hero-sheet,
.section,
.article-card,
.guide-card {
  animation: rise-in 420ms ease both;
}

@keyframes rise-in {
  from {
    opacity: 0;
    transform: translateY(10px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 1180px) {
  .signal-panel {
    grid-template-columns: 1fr;
  }

  .doc-layout {
    grid-template-columns: 1fr;
  }

  .guide-card {
    position: static;
  }
}

@media (max-width: 980px) {
  .doc-shell {
    display: block;
  }

  .doc-sidebar {
    display: none;
  }

  .doc-main {
    padding-top: 22px;
  }

  .mobile-doc-directory {
    display: block;
  }
}

@media (max-width: 860px) {
  .home-shell {
    width: min(100%, calc(100% - 28px));
    padding-top: 16px;
  }

  .masthead,
  .doc-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .hero {
    grid-template-columns: 1fr;
  }

  .hero-main h1 {
    max-width: none;
    font-size: clamp(1.8rem, 8vw, 2.5rem);
    line-height: 1.16;
  }

  .signal-row {
    grid-template-columns: 1fr;
    gap: 10px;
  }
}

@media (max-width: 640px) {
  .hero-main,
  .hero-sheet,
  .signal-panel,
  .metric-card,
  .feature-card,
  .timeline-card,
  .download-card,
  .article-card,
  .guide-card {
    border-radius: 22px;
  }

  .hero-main,
  .hero-sheet,
  .signal-panel {
    padding: 18px;
  }

  .metric-card,
  .feature-card,
  .timeline-card,
  .download-card {
    padding: 18px;
  }

  .article-card {
    padding: 18px;
  }

  .doc-main {
    padding-left: 14px;
    padding-right: 14px;
  }

  .doc-sidebar {
    padding: 22px 14px;
  }

  .mobile-doc-directory summary {
    padding: 14px 16px;
  }

  .mobile-doc-nav {
    padding: 0 12px 12px;
  }

  .prose th,
  .prose td {
    min-width: 120px;
    padding: 10px 12px;
    font-size: 0.94rem;
  }

  .section {
    margin-top: 18px;
  }

  .section-heading {
    margin-bottom: 14px;
  }

  .section-heading h2 {
    margin: 6px 0 10px;
    font-size: clamp(1.35rem, 6vw, 1.8rem);
    line-height: 1.22;
  }

  .section-heading p,
  .hero-main p,
  .path-step p,
  .metric-card p,
  .feature-card p,
  .timeline-card p,
  .download-card p {
    line-height: 1.74;
  }
}