:root {
  --color-surface: #fbfbfb;
  --color-surface-alt: #f1f1f1;
  --color-surface-deep: #e3e3e3;
  --color-ink: #2f3437;
  --color-ink-soft: #5a6267;
  --color-ink-muted: #737b81;
  --color-line: #d6d7d8;
  --color-primary: #0a78cc;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #d9e9f4;
  --color-accent: #438307;
  --color-accent-ink: #ffffff;
  --color-highlight: #dae5cf;
  --color-focus: #3e8000;
  --color-contrast-surface: #101d26;
  --color-contrast-ink: #e4e6e7;
  --color-contrast-line: #3f4950;
  --color-contrast-accent: #7df20d;
  --overlay-scrim: linear-gradient(180deg, rgba(16, 29, 38, 0.35) 0%, rgba(16, 29, 38, 0.72) 55%, rgba(16, 29, 38, 0.92) 100%);
  --font-heading: "Source Han Sans SC", "Noto Sans SC", SimHei, "Microsoft YaHei", sans-serif;
  --font-body: "PingFang SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 9.3px;
  --text-sm: 13.9px;
  --text-base: 17px;
  --text-lg: 25.5px;
  --text-xl: 38.2px;
  --text-2xl: 57.4px;
  --text-3xl: 86.1px;
  --text-4xl: 129.1px;
  --text-display: clamp(38px, 7.9vw, 101px);
  --text-figure: clamp(32px, 5.7vw, 73px);
  --weight-heading: 878;
  --weight-body: 400;
  --leading-body: 1.66;
  --leading-heading: 1.16;
  --tracking-heading: -0.014em;
  --radius-sm: 150px;
  --radius-md: 293px;
  --radius-lg: 436px;
  --radius-pill: 999px;
  --border-thin: 2px;
  --border-thick: 3px;
  --shadow-1: none;
  --shadow-2: none;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1160px;
  --measure: 69ch;
  --gutter: 24px;
  --section-y: 82px;
  --section-y-lg: 115px;
}

/* ============================================================
   reset
   ============================================================ */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  font-weight: var(--weight-body);
  -webkit-font-smoothing: antialiased;
}

img,
svg,
video { display: block; max-width: 100%; height: auto; }

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

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

ul,
ol { margin: 0; padding: 0; list-style: none; }

h1, h2, h3, h4, h5, h6, p, figure, blockquote { margin: 0; }

::selection {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

/* ============================================================
   中文排版
   ============================================================ */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  text-wrap: balance;
}

p {
  max-width: var(--measure);
  text-wrap: pretty;
}

strong, b { font-weight: var(--weight-heading); }

/* ============================================================
   布局骨架
   ============================================================ */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--space-3);
}

.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }
.section--tight { padding-block: var(--space-8); }

.grid {
  display: grid;
  grid-template-columns: repeat(9, minmax(0, 1fr));
  gap: var(--gutter);
}

.stack > * + * { margin-top: var(--space-3); }

/* ============================================================
   skip link
   ============================================================ */
.skip-link {
  position: fixed;
  top: var(--space-2);
  left: var(--space-2);
  z-index: 200;
  transform: translateY(-240%);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  padding: 12px 26px;
  border-radius: var(--radius-pill);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  transition: transform .18s ease;
}

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

/* ============================================================
   头部：悬浮胶囊导航
   ============================================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  padding: var(--space-3) var(--space-2) 0;
  pointer-events: none;
}

.site-header__inner {
  pointer-events: auto;
  position: relative;
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-2) var(--space-2) var(--space-4);
  background: color-mix(in srgb, var(--color-surface) 94%, transparent);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-pill);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  transition: padding .22s ease, border-color .22s ease;
}

.site-header.is-condensed .site-header__inner {
  padding-top: 8px;
  padding-bottom: 8px;
  border-color: color-mix(in srgb, var(--color-line) 70%, var(--color-primary));
}

/* 品牌：圆 + 方几何短标 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  flex: 0 0 auto;
}

.brand__mark {
  position: relative;
  display: block;
  width: 36px;
  height: 36px;
  flex: 0 0 auto;
}

.brand__mark::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 24px;
  height: 24px;
  border-radius: var(--radius-lg);
  background: var(--color-primary);
}

.brand__mark::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  width: 17px;
  height: 17px;
  background: var(--color-accent);
}

.brand__word {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  letter-spacing: var(--tracking-heading);
  line-height: 1;
  transition: font-size .22s ease;
}

.site-header.is-condensed .brand__word { font-size: var(--text-base); }

/* 移动按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--space-1);
  padding: 10px 20px;
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid var(--color-line);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
  transition: background-color .2s ease, border-color .2s ease;
}

.nav-toggle:hover,
.nav-toggle[aria-expanded="true"] {
  background: var(--color-primary-soft);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.nav-toggle__label { line-height: 1; }

.nav-toggle__bars {
  display: inline-grid;
  gap: 4px;
  width: 18px;
}

.nav-toggle__bars i {
  display: block;
  height: var(--border-thin);
  background: currentColor;
}

.nav-toggle__bars i:last-child {
  width: 62%;
  justify-self: end;
}

/* 导航 */
.nav { display: flex; align-items: center; }

.nav__list {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.nav__link {
  display: inline-block;
  padding: 10px 18px;
  border-radius: var(--radius-pill);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: var(--text-sm);
  line-height: 1.2;
  color: var(--color-ink-soft);
  white-space: nowrap;
  transition: background-color .2s ease, color .2s ease;
}

.nav__link:hover {
  background: var(--color-primary-soft);
  color: var(--color-primary);
}

.nav__link[aria-current="page"] {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  font-weight: var(--weight-heading);
}

/* ============================================================
   页脚：反色 + 超大品牌字标 + 横向胶囊路由带
   ============================================================ */
.site-footer {
  position: relative;
  overflow: hidden;
  margin-top: var(--section-y-lg);
  padding-block: var(--section-y-lg) var(--space-6);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -140px;
  right: -70px;
  width: 300px;
  height: 300px;
  border-radius: var(--radius-lg);
  background: var(--color-primary);
  opacity: .26;
  pointer-events: none;
}

.site-footer::after {
  content: "";
  position: absolute;
  bottom: -160px;
  left: -90px;
  width: 340px;
  height: 340px;
  border-radius: var(--radius-lg);
  background: var(--color-accent);
  opacity: .22;
  pointer-events: none;
}

.site-footer__inner {
  position: relative;
  z-index: 1;
}

.footer__wordmark {
  max-width: none;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: clamp(var(--text-2xl), 8vw, var(--text-3xl));
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
}

.footer__note {
  margin-top: var(--space-3);
  max-width: 48ch;
  font-size: var(--text-base);
  color: var(--color-contrast-ink);
  opacity: .74;
}

.footer__routes {
  margin-top: var(--space-8);
  overflow-x: auto;
  padding-bottom: var(--space-2);
  scrollbar-width: thin;
  scrollbar-color: var(--color-contrast-line) transparent;
  -webkit-overflow-scrolling: touch;
}

.footer__route-list {
  display: flex;
  gap: var(--space-2);
  min-width: max-content;
}

.footer__chip {
  display: inline-block;
  padding: 12px 24px;
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-pill);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: var(--text-sm);
  line-height: 1.2;
  color: var(--color-contrast-ink);
  white-space: nowrap;
  transition: background-color .2s ease, color .2s ease, border-color .2s ease;
}

.footer__chip:hover {
  background: var(--color-contrast-accent);
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

.footer__legal {
  margin-top: var(--space-6);
  padding-top: var(--space-4);
  border-top: var(--border-thin) solid var(--color-contrast-line);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-6);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
}

.footer__legal-item { opacity: .7; }

/* ============================================================
   按钮
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  padding: 15px 32px;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-pill);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-base);
  line-height: 1;
  transition: background-color .2s ease, color .2s ease, border-color .2s ease;
}

.btn--primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.btn--primary:hover {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.btn--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.btn--accent:hover {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.btn--ghost {
  border-color: var(--color-line);
  color: var(--color-ink);
}

.btn--ghost:hover {
  background: var(--color-primary-soft);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.btn--onDark {
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}

.btn--onDark:hover {
  background: var(--color-contrast-accent);
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

/* ============================================================
   面包屑
   ============================================================ */
.breadcrumb {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
}

.breadcrumb li {
  display: inline-flex;
  align-items: center;
}

.breadcrumb li:not(:first-child)::before {
  content: "／";
  margin-inline-end: var(--space-1);
  color: var(--color-line);
}

.breadcrumb a:hover { color: var(--color-primary); }

/* ============================================================
   文字组件
   ============================================================ */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--color-primary);
}

.eyebrow::before {
  content: "";
  width: 10px;
  height: 10px;
  border-radius: var(--radius-pill);
  background: currentColor;
  flex: 0 0 auto;
}

.eyebrow--accent { color: var(--color-accent); }

.section-title {
  font-size: clamp(var(--text-xl), 4vw, var(--text-2xl));
  max-width: 20ch;
}

.lede {
  font-size: var(--text-lg);
  line-height: 1.42;
  color: var(--color-ink-soft);
  max-width: var(--measure);
}

.prose { max-width: var(--measure); }

.prose > * + * { margin-top: var(--space-3); }

.prose h2 {
  margin-top: var(--space-8);
  font-size: clamp(var(--text-lg), 3vw, var(--text-xl));
}

.prose h3 {
  margin-top: var(--space-6);
  font-size: var(--text-lg);
}

.prose ul,
.prose ol {
  max-width: var(--measure);
  padding-left: var(--space-3);
}

.prose ul li { list-style: square; }
.prose ol li { list-style: decimal; }
.prose li + li { margin-top: var(--space-1); }

.prose a {
  color: var(--color-primary);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-thickness: var(--border-thin);
  text-underline-offset: 4px;
}

.num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  letter-spacing: -.01em;
}

/* ============================================================
   几何分区 / 面板
   ============================================================ */
.panel {
  padding: var(--space-6);
  border-radius: var(--radius-md);
  background: var(--color-surface-alt);
}

.panel--primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}

.panel--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.panel--highlight {
  background: var(--color-highlight);
  color: var(--color-ink);
}

.panel--deep {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.panel--deep .eyebrow { color: var(--color-contrast-accent); }
.panel--primary .eyebrow,
.panel--accent .eyebrow { color: var(--color-primary-ink); }

/* ============================================================
   索引行
   ============================================================ */
.index-list { display: grid; }

.index-row {
  display: grid;
  grid-template-columns: 64px minmax(160px, .7fr) minmax(0, 1.6fr);
  gap: var(--space-2) var(--space-4);
  align-items: start;
  padding-block: var(--space-4);
}

.index-row__num {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-primary);
  padding-top: 4px;
}

.index-row__label {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-lg);
  line-height: 1.24;
}

.index-row__desc {
  color: var(--color-ink-soft);
  max-width: 54ch;
}

.index-list--alt .index-row__num { color: var(--color-accent); }

/* ============================================================
   标签
   ============================================================ */
.tag {
  display: inline-block;
  padding: 6px 18px;
  border-radius: var(--radius-pill);
  background: var(--color-surface-deep);
  color: var(--color-ink-soft);
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: var(--text-sm);
  line-height: 1.4;
}

.tag--primary {
  background: var(--color-primary-soft);
  color: var(--color-primary);
}

.tag--accent {
  background: var(--color-highlight);
  color: var(--color-accent);
}

/* ============================================================
   数据表
   ============================================================ */
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-base);
}

.data-table caption {
  text-align: left;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--color-ink-muted);
  padding-bottom: var(--space-2);
}

.data-table th {
  text-align: left;
  padding: var(--space-2) var(--space-3);
  background: var(--color-surface-deep);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: var(--text-sm);
}

.data-table td {
  padding: var(--space-3);
  border-bottom: var(--border-thin) solid var(--color-line);
  vertical-align: top;
}

.data-table td.numeric {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

.data-table tbody tr:hover { background: var(--color-primary-soft); }

/* ============================================================
   图片容器
   ============================================================ */
.media-frame {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  border-radius: var(--radius-md);
  background: var(--color-contrast-surface);
  min-height: 260px;
}

.media-frame__img {
  width: 100%;
  height: 100%;
  min-height: inherit;
  object-fit: cover;
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  background: var(--overlay-scrim);
  pointer-events: none;
}

.media-frame__body {
  position: absolute;
  inset: auto 0 0 0;
  z-index: 2;
  padding: var(--space-6);
  color: var(--color-contrast-ink);
}

.media-frame__body .eyebrow { color: var(--color-contrast-accent); }

.media-frame--plain::after { display: none; }

/* ============================================================
   统计条
   ============================================================ */
.stat-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: var(--space-6);
  padding-block: var(--space-6);
}

.stat__value {
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  font-weight: 700;
  line-height: .96;
  letter-spacing: -.03em;
  font-variant-numeric: tabular-nums;
  color: var(--color-primary);
}

.stat--accent .stat__value { color: var(--color-accent); }

.stat__label {
  margin-top: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}

.panel--deep .stat__value { color: var(--color-contrast-accent); }
.panel--deep .stat__label { color: var(--color-contrast-ink); opacity: .66; }

/* ============================================================
   滚动进度
   ============================================================ */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 120;
  width: 0;
  height: var(--border-thick);
  background: var(--color-primary);
  pointer-events: none;
  transition: width .08s linear;
}

/* ============================================================
   焦点与动效降级
   ============================================================ */
:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 3px;
}

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

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }

  .scroll-progress { transition: none; }
}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1080px) {
  .nav__link { padding: 10px 14px; }
  .brand__word { font-size: var(--text-base); }
}

@media (max-width: 900px) {
  .section { padding-block: var(--space-8); }
  .section--lg { padding-block: var(--space-8); }

  .site-footer {
    margin-top: var(--space-8);
    padding-block: var(--space-8) var(--space-6);
  }

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

  .site-header { padding: var(--space-2) var(--space-2) 0; }

  .site-header__inner {
    padding: 12px 12px 12px var(--space-3);
  }

  .site-header.is-condensed .site-header__inner {
    padding-top: 10px;
    padding-bottom: 10px;
  }

  .nav-toggle { display: inline-flex; }

  .nav {
    position: absolute;
    top: calc(100% + var(--space-1));
    left: 0;
    right: 0;
    display: none;
    padding: var(--space-2);
    background: var(--color-surface);
    border: var(--border-thin) solid var(--color-line);
    border-radius: var(--radius-sm);
  }

  .nav[data-open] { display: block; }

  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-1);
  }

  .nav__link {
    display: block;
    text-align: left;
    padding: 14px 22px;
    font-size: var(--text-base);
  }

  .index-row {
    grid-template-columns: 48px minmax(0, 1fr);
    gap: var(--space-1) var(--space-3);
  }

  .index-row__desc {
    grid-column: 2 / -1;
    font-size: var(--text-base);
  }

  .stat-strip { gap: var(--space-4); }
}

@media (max-width: 560px) {
  .grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }

  .container { padding-inline: var(--space-2); }

  .panel { padding: var(--space-4); border-radius: var(--radius-sm); }

  .media-frame { border-radius: var(--radius-sm); min-height: 200px; }

  .media-frame__body { padding: var(--space-4); }

  .footer__legal { font-size: var(--text-xs); }

  .btn { width: 100%; }
}

@media (min-width: 901px) {
  .nav { display: flex; }
}