/* ============================================================
   体验体育 · K1 体育数据与观赛服务
   共享样式表 /assets/site.css
   世界观：夜场数据面板 —— 深墨绿底、荧光青数据光、橙红行动点
   ============================================================ */

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body, h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, dl, dd, hr {
  margin: 0;
  padding: 0;
}

ul, ol { list-style: none; }

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

button, input, select, textarea { font: inherit; color: inherit; }

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

hr { border: 0; }

/* ---------- 2. 设计令牌 ---------- */
:root {
  --ink-night: #061512;
  --deep-pitch: #0B2B24;
  --pitch-layer: #10453A;
  --cyan-signal: #37F5C8;
  --cyan-deep: #12B58F;
  --signal-orange: #FF5A1F;
  --amber-tick: #FFB020;
  --paper-light: #F2F5F1;
  --paper-mute: #D7E2DA;
  --line-graphite: #2A4740;
  --text-on-dark: #E8F2EC;
  --text-on-paper: #0A201B;

  --frame-h: 72px;
  --rail-w: 88px;
  --rail-h: 46px;
  --gutter: 24px;
  --maxw: 1280px;
  --radius: 4px;

  --font-head: "PingFang SC", "Hiragino Sans GB", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Source Han Sans SC", "Noto Sans SC", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;

  --ease: cubic-bezier(.22, .61, .36, 1);
}

/* ---------- 3. 基础排版 ---------- */
body {
  padding-top: calc(var(--frame-h) + var(--rail-h));
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.55;
  font-weight: 400;
  color: var(--text-on-dark);
  background-color: var(--ink-night);
  background-image:
    radial-gradient(1200px 600px at 78% -10%, rgba(18, 181, 143, .12), transparent 70%),
    radial-gradient(900px 500px at 8% 100%, rgba(55, 245, 200, .07), transparent 72%);
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--font-head);
  font-weight: 800;
  letter-spacing: -.015em;
  line-height: 1.12;
}

h1 { font-size: clamp(34px, 5.4vw, 68px); }
h2 { font-size: clamp(26px, 3.6vw, 48px); }
h3 { font-size: clamp(20px, 2.4vw, 26px); }

p { max-width: 72ch; }

::selection {
  background: var(--cyan-signal);
  color: var(--ink-night);
}

:focus-visible {
  outline: 2px solid var(--signal-orange);
  outline-offset: 3px;
  border-radius: 2px;
}

/* ---------- 4. 通用工具 ---------- */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.mono {
  font-family: var(--font-mono);
  letter-spacing: -.01em;
}

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

.lead {
  font-size: 18px;
  line-height: 1.6;
  color: var(--text-on-dark);
}

.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--cyan-signal);
  border-left: 2px solid var(--cyan-signal);
  padding-left: 8px;
  margin-bottom: 14px;
}

.display-thin {
  font-family: var(--font-head);
  font-weight: 200;
  font-size: clamp(46px, 8.6vw, 96px);
  line-height: 1.02;
  letter-spacing: -.03em;
  color: var(--text-on-dark);
}

/* ---------- 5. 布局容器 ---------- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding-left: clamp(16px, 3.4vw, 40px);
  padding-right: clamp(16px, 3.4vw, 40px);
}

.section {
  padding-top: clamp(56px, 8vw, 120px);
  padding-bottom: clamp(56px, 8vw, 120px);
}

.section--tight {
  padding-top: clamp(28px, 4vw, 56px);
  padding-bottom: clamp(28px, 4vw, 56px);
}

.rule {
  display: block;
  height: 1px;
  width: 100%;
  background: var(--line-graphite);
}

.grid {
  display: grid;
  gap: var(--gutter);
  grid-template-columns: 1fr;
}

.split {
  display: grid;
  gap: var(--gutter);
  grid-template-columns: 1fr;
}

@media (min-width: 700px) {
  .grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 900px) {
  .grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .split { grid-template-columns: 5fr 7fr; }
  .split--reverse { grid-template-columns: 7fr 5fr; }
}

@media (min-width: 1120px) {
  .grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

.band {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px 22px;
  min-height: 120px;
  padding: 24px clamp(16px, 3.4vw, 40px);
  background: var(--deep-pitch);
  border-top: 1px solid var(--line-graphite);
  border-bottom: 1px solid var(--line-graphite);
}

.band__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--cyan-signal);
  text-transform: uppercase;
}

.band__list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 6. 区块标题组 ---------- */
.section-head { margin-bottom: clamp(22px, 3vw, 40px); }

.section-head__index {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--cyan-deep);
  margin-bottom: 10px;
}

.section-head__title {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: clamp(30px, 4.4vw, 68px);
  line-height: 1.08;
  letter-spacing: -.025em;
  color: var(--text-on-dark);
}

.section-head__note {
  margin-top: 12px;
  font-size: 15px;
  line-height: 1.6;
  color: var(--paper-mute);
}

/* ---------- 7. 标签与按钮 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 11px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--cyan-signal);
  background: rgba(55, 245, 200, .08);
  border: 2px solid var(--cyan-signal);
  border-radius: var(--radius);
  white-space: nowrap;
}

.tag--amber {
  color: var(--amber-tick);
  background: rgba(255, 176, 32, .1);
  border-color: var(--amber-tick);
}

.tag--cyan {
  color: var(--ink-night);
  background: var(--cyan-signal);
  border-color: var(--cyan-signal);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: .04em;
  line-height: 1;
  border: 2px solid var(--cyan-signal);
  border-radius: var(--radius);
  color: var(--cyan-signal);
  background: transparent;
  cursor: pointer;
  transition: background-color .22s var(--ease), color .22s var(--ease), border-color .22s var(--ease), transform .22s var(--ease);
}

.btn:hover {
  background: rgba(55, 245, 200, .14);
  transform: translateY(-1px);
}

.btn--signal {
  color: #170700;
  background: var(--signal-orange);
  border-color: var(--signal-orange);
}

.btn--signal:hover {
  background: #FF7038;
  border-color: #FF7038;
}

.btn--ghost {
  border-color: var(--line-graphite);
  color: var(--text-on-dark);
}

.btn--ghost:hover {
  border-color: var(--cyan-signal);
  color: var(--cyan-signal);
  background: rgba(55, 245, 200, .08);
}

.btn--sm {
  padding: 8px 14px;
  font-size: 13px;
  border-radius: 3px;
}

.btn--lg {
  padding: 16px 32px;
  font-size: 17px;
}

.btn--block {
  display: flex;
  width: 100%;
}

/* ---------- 8. 档案卡 ---------- */
.archive-card {
  position: relative;
  padding: 22px 24px 24px;
  color: var(--text-on-paper);
  background: var(--paper-light);
  border: 2px solid var(--line-graphite);
  border-radius: var(--radius);
  box-shadow: 8px 8px 0 -1px var(--deep-pitch), 8px 8px 0 0 var(--line-graphite);
  transition: transform .24s var(--ease), box-shadow .24s var(--ease);
}

.archive-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: 12px 12px 0 -1px var(--deep-pitch), 12px 12px 0 0 var(--cyan-deep);
}

.archive-card__num {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--text-on-paper);
  background: var(--amber-tick);
  padding: 3px 8px;
  border-radius: 2px;
  margin-bottom: 14px;
}

.archive-card__title {
  font-family: var(--font-head);
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -.01em;
  margin-bottom: 8px;
}

.archive-card__text {
  font-size: 14px;
  line-height: 1.6;
  color: #23423A;
}

.archive-card__foot {
  margin-top: 16px;
  padding-top: 12px;
  border-top: 1px solid var(--paper-mute);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: #3A5A51;
}

/* ---------- 9. 数据图形 ---------- */
.data-figure {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.data-figure__value {
  display: inline-block;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: clamp(56px, 9vw, 140px);
  line-height: .92;
  letter-spacing: -.04em;
  color: var(--cyan-signal);
  border-bottom: 2px solid rgba(55, 245, 200, .45);
  padding-bottom: 4px;
}

.data-figure__unit {
  font-family: var(--font-mono);
  font-size: 14px;
  letter-spacing: .16em;
  color: var(--cyan-deep);
}

.data-figure__label {
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--paper-mute);
}

/* ---------- 10. 数据表 ---------- */
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

.data-table th,
.data-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--line-graphite);
}

.data-table thead th {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--cyan-deep);
  border-bottom: 2px solid var(--line-graphite);
}

.data-table tbody tr:nth-child(even) { background: rgba(16, 69, 58, .28); }

.data-table tbody tr:hover {
  background: var(--pitch-layer);
  box-shadow: inset 3px 0 0 0 var(--signal-orange);
}

.data-table__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--ink-night);
  background: var(--cyan-signal);
  padding: 2px 6px;
  border-radius: 2px;
}

/* ---------- 11. 图像容器 ---------- */
.media {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: var(--deep-pitch);
  border: 2px solid var(--line-graphite);
  border-radius: var(--radius);
}

.media__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.35) contrast(1.06) brightness(.82);
}

.media--wide { aspect-ratio: 21 / 9; }
.media--tall { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }

.media__tag {
  position: absolute;
  top: 12px;
  left: 12px;
  z-index: 2;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .12em;
  color: var(--ink-night);
  background: var(--cyan-signal);
  padding: 4px 9px;
  border-radius: 2px;
}

.media__caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  padding: 26px 14px 12px;
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--paper-light);
  background: linear-gradient(180deg, rgba(6, 21, 18, 0), rgba(6, 21, 18, .9));
}

/* ---------- 12. 面包屑 ---------- */
.breadcrumb {
  padding-top: 22px;
  padding-bottom: 4px;
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
}

.breadcrumb__item { display: inline-flex; align-items: center; gap: 8px; }

.breadcrumb__link {
  color: var(--cyan-deep);
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.breadcrumb__link:hover {
  color: var(--cyan-signal);
  border-color: var(--cyan-signal);
}

.breadcrumb__sep { color: var(--line-graphite); }

.breadcrumb__current { color: var(--text-on-dark); }

/* ---------- 13. 页头：框架条 + 索引轨 ---------- */
.skip-link {
  position: absolute;
  left: 16px;
  top: -72px;
  z-index: 140;
  padding: 10px 18px;
  font-size: 14px;
  font-weight: 700;
  color: #170700;
  background: var(--signal-orange);
  border-radius: var(--radius);
  transition: top .2s var(--ease);
}

.skip-link:focus {
  top: 12px;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 80;
  background: var(--deep-pitch);
}

.frame-bar {
  position: relative;
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
  height: var(--frame-h);
  padding: 0 clamp(14px, 3vw, 36px);
  background: var(--deep-pitch);
  border-bottom: 1px solid var(--line-graphite);
}

.brand { flex: 0 0 auto; }

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

.brand__mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .02em;
  color: var(--cyan-signal);
  border: 2px solid var(--cyan-signal);
  border-radius: var(--radius);
  background: linear-gradient(160deg, rgba(55, 245, 200, .18), rgba(55, 245, 200, 0));
}

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.24;
}

.brand__name {
  font-family: var(--font-head);
  font-size: 15px;
  font-weight: 800;
  letter-spacing: .08em;
  color: var(--text-on-dark);
}

.brand__sub {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .1em;
  color: var(--cyan-deep);
}

.main-nav {
  flex: 1 1 auto;
  display: flex;
  justify-content: center;
}

.main-nav__list {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 2px;
}

.main-nav__item { display: block; }

.main-nav__link {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 12px;
  font-size: 14px;
  letter-spacing: .03em;
  color: var(--text-on-dark);
  border-radius: var(--radius);
  transition: color .22s var(--ease);
}

.main-nav__index {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .08em;
  color: var(--cyan-deep);
  transition: color .22s var(--ease);
}

.main-nav__link::after {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: 2px;
  height: 2px;
  background: var(--cyan-signal);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform .28s var(--ease);
}

.main-nav__link:hover,
.main-nav__link:focus-visible { color: var(--cyan-signal); }

.main-nav__link:hover .main-nav__index,
.main-nav__link:focus-visible .main-nav__index { color: var(--cyan-signal); }

.main-nav__link:hover::after,
.main-nav__link:focus-visible::after,
.main-nav__link[aria-current="page"]::after { transform: scaleX(1); }

.main-nav__link[aria-current="page"] { color: var(--cyan-signal); }
.main-nav__link[aria-current="page"] .main-nav__index { color: var(--cyan-signal); }

.frame-bar__actions {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 9px 13px;
  font-family: var(--font-head);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .08em;
  color: var(--text-on-dark);
  background: transparent;
  border: 2px solid var(--line-graphite);
  border-radius: var(--radius);
  cursor: pointer;
  transition: border-color .22s var(--ease), color .22s var(--ease);
}

.nav-toggle:hover { border-color: var(--cyan-signal); color: var(--cyan-signal); }

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 16px;
  height: 2px;
  background: currentColor;
}

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 2px;
  background: currentColor;
  transition: transform .24s var(--ease), top .24s var(--ease);
}

.nav-toggle__bars::before { top: -5px; }
.nav-toggle__bars::after { top: 5px; }

.nav-toggle[aria-expanded="true"] .nav-toggle__bars { background: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { top: 0; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after { top: 0; transform: rotate(-45deg); }

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

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: rgba(55, 245, 200, .12);
  overflow: hidden;
}

.scroll-progress__bar {
  display: block;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, var(--cyan-signal), var(--amber-tick));
  transform: scaleX(0);
  transform-origin: left center;
}

/* 桌面端：纵向索引轨 —— 导航成为页面左边框 */
.index-rail {
  position: fixed;
  top: var(--frame-h);
  left: 0;
  bottom: 0;
  width: var(--rail-w);
  z-index: 70;
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 20px 0 18px;
  background: linear-gradient(180deg, var(--deep-pitch), var(--ink-night) 62%);
  border-right: 1px solid var(--line-graphite);
  overflow-y: auto;
}

.index-rail__label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .28em;
  text-align: center;
  color: var(--cyan-deep);
}

.index-rail__list {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.index-rail__item { display: block; }

.index-rail__link {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 11px 4px;
  font-size: 12px;
  letter-spacing: .04em;
  color: var(--text-on-dark);
  transition: color .22s var(--ease), background-color .22s var(--ease);
}

.index-rail__link::before {
  content: "";
  width: 6px;
  height: 6px;
  background: transparent;
  border: 1px solid var(--line-graphite);
  transition: background-color .22s var(--ease), border-color .22s var(--ease);
}

.index-rail__num {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: .1em;
  color: var(--cyan-deep);
}

.index-rail__text { white-space: nowrap; }

.index-rail__link:hover {
  color: var(--cyan-signal);
  background: rgba(55, 245, 200, .07);
}

.index-rail__link:hover::before { border-color: var(--cyan-signal); }

.index-rail__link[aria-current="page"] { color: var(--cyan-signal); }

.index-rail__link[aria-current="page"]::before {
  background: var(--cyan-signal);
  border-color: var(--cyan-signal);
}

.index-rail__link[aria-current="page"] .index-rail__num { color: var(--cyan-signal); }

/* ---------- 14. 页脚 ---------- */
.site-footer {
  margin-top: clamp(56px, 8vw, 120px);
  color: var(--text-on-dark);
  background: var(--deep-pitch);
  border-top: 1px solid var(--line-graphite);
}

.site-footer__inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: clamp(36px, 5vw, 68px) clamp(16px, 3.4vw, 40px) clamp(28px, 4vw, 46px);
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1.35fr 1fr;
  gap: clamp(20px, 3vw, 40px);
}

.site-footer__brand { min-width: 0; }

.site-footer__mark {
  display: inline-grid;
  place-items: center;
  width: 40px;
  height: 40px;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--cyan-signal);
  border: 2px solid var(--cyan-signal);
  border-radius: var(--radius);
  margin-bottom: 14px;
}

.site-footer__name {
  font-family: var(--font-head);
  font-size: 20px;
  font-weight: 800;
  letter-spacing: .08em;
  margin-bottom: 10px;
}

.site-footer__tag {
  font-size: 13px;
  line-height: 1.6;
  color: var(--paper-mute);
  max-width: 30ch;
}

.site-footer__basis {
  margin-top: 14px;
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--amber-tick);
  border-left: 2px solid var(--amber-tick);
  padding-left: 8px;
}

.footer-col { min-width: 0; }

.footer-col__title {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: .16em;
  color: var(--cyan-signal);
  margin-bottom: 14px;
}

.footer-col__list {
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.footer-col__item { display: block; }

.footer-col__link {
  display: inline-block;
  font-size: 14px;
  color: var(--paper-mute);
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.footer-col__link:hover {
  color: var(--cyan-signal);
  border-color: var(--cyan-signal);
}

.footer-col__list--meta { gap: 12px; }

.footer-col__meta {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.footer-col__meta-key {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--cyan-deep);
}

.footer-col__meta-value {
  font-size: 13px;
  line-height: 1.5;
  color: var(--paper-mute);
  word-break: break-word;
}

.site-footer__legal {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 18px clamp(16px, 3.4vw, 40px) 34px;
  border-top: 1px solid var(--line-graphite);
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 28px;
}

.site-footer__legal-line {
  font-size: 12px;
  line-height: 1.6;
  color: var(--paper-mute);
}

.site-footer__copy {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .08em;
  color: var(--cyan-deep);
}

/* ---------- 15. 响应式 ---------- */
@media (min-width: 961px) {
  body {
    padding-top: var(--frame-h);
    padding-left: var(--rail-w);
  }
}

@media (max-width: 1100px) {
  .site-footer__inner {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
  .site-footer__brand { grid-column: 1 / -1; }
}

@media (max-width: 960px) {
  .nav-toggle { display: inline-flex; }

  .main-nav {
    display: none;
    flex: 0 0 auto;
  }

  .main-nav[data-open] {
    display: block;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 6;
    max-height: 72vh;
    overflow-y: auto;
    padding: 10px clamp(14px, 4vw, 28px) 20px;
    background: var(--deep-pitch);
    border-bottom: 1px solid var(--line-graphite);
  }

  .main-nav[data-open] .main-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .main-nav[data-open] .main-nav__link {
    display: flex;
    justify-content: flex-start;
    padding: 15px 6px;
    font-size: 16px;
    border-bottom: 1px solid var(--line-graphite);
    border-radius: 0;
  }

  .main-nav[data-open] .main-nav__link::after {
    left: 6px;
    right: auto;
    bottom: 0;
    width: 0;
    transform: none;
    transition: width .28s var(--ease);
  }

  .main-nav[data-open] .main-nav__link:hover::after,
  .main-nav[data-open] .main-nav__link:focus-visible::after,
  .main-nav[data-open] .main-nav__link[aria-current="page"]::after {
    width: 34px;
  }

  /* 索引轨收为顶部横向滚动标签带 */
  .index-rail {
    position: static;
    width: auto;
    height: var(--rail-h);
    flex-direction: row;
    align-items: center;
    gap: 0;
    padding: 0;
    border-right: 0;
    border-bottom: 1px solid var(--line-graphite);
    background: var(--ink-night);
    overflow-x: auto;
    overflow-y: hidden;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: thin;
  }

  .index-rail__label { display: none; }

  .index-rail__list {
    flex-direction: row;
    align-items: center;
    gap: 4px;
    height: 100%;
    padding: 0 14px;
  }

  .index-rail__link {
    flex-direction: row;
    align-items: center;
    gap: 6px;
    padding: 6px 10px;
    font-size: 12px;
  }

  .index-rail__link::before { width: 5px; height: 5px; }
}

@media (max-width: 900px) {
  .split,
  .split--reverse { grid-template-columns: 1fr; }
  .grid--3,
  .grid--4 { grid-template-columns: 1fr; }
}

@media (max-width: 720px) {
  .brand__sub { display: none; }

  .btn--sm { padding: 7px 11px; font-size: 12px; }

  .frame-bar__actions .btn--signal { display: none; }

  .site-footer__copy {
    margin-left: 0;
  }
}

@media (max-width: 640px) {
  .site-footer__inner { grid-template-columns: 1fr; }
}

/* ---------- 16. 动效协议 ---------- */
html[data-motion="on"] [data-reveal] {
  opacity: 0;
  transform: translate3d(0, 12px, 0);
}

html[data-motion="on"] [data-reveal].is-revealed {
  opacity: 1;
  transform: none;
  transition: opacity .4s var(--ease), transform .4s var(--ease);
}

@media (prefers-reduced-motion: reduce) {
  html[data-motion="on"] [data-reveal],
  html[data-motion="on"] [data-reveal].is-revealed {
    opacity: 1;
    transform: none;
    transition: none;
  }

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