/* ==========================================================================
   B体育官方品牌站 — /assets/site.css
   共享层：reset / 变量 / 中文排版 / 头部 / 页脚 / 通用组件
   设计语言：夜幕炭黑场地 + 暖沙金场灯 + 荧光青数据高亮
   ========================================================================== */

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

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

body, h1, h2, h3, h4, p, ul, ol, li, figure, blockquote, dl, dd { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; height: auto; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }
[hidden] { display: none !important; }

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

/* ---------- 2. 变量 ---------- */
:root {
  --night: #0B0D10;
  --slate: #14171C;
  --panel: #1D2127;
  --line: #2C3138;
  --gold: #C9A227;
  --sand: #E7CD8B;
  --cyan: #63F5D2;
  --ink: #EDEAE3;
  --muted: #9AA1AA;
  --umber: #3A2F16;

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

  --radius: 4px;
  --shell: 1200px;
  --gutter: clamp(16px, 4vw, 28px);
  --header-h: 72px;
  --ease: cubic-bezier(0.4, 0.16, 0.2, 1);
  --dur: 260ms;
}

@media (max-width: 960px) {
  :root { --header-h: 60px; }
}

/* ---------- 3. 基础与中文排版 ---------- */
body {
  min-height: 100%;
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink);
  letter-spacing: 0.01em;
  background-color: var(--night);
  background-image:
    radial-gradient(760px 500px at 84% -12%, rgba(201, 162, 39, 0.10), transparent 62%),
    radial-gradient(640px 440px at -8% 8%, rgba(99, 245, 210, 0.05), transparent 66%),
    linear-gradient(180deg, #0B0D10 0%, #0B0D10 44%, #101319 100%);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

:where(section, [id]) { scroll-margin-top: calc(var(--header-h) + 18px); }

strong, b { font-weight: 700; color: var(--ink); }
::selection { background: rgba(201, 162, 39, 0.32); color: #fff; }

/* ---------- 4. 布局骨架 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: clamp(44px, 7vw, 88px); }
.section--tight { padding-block: clamp(26px, 4vw, 48px); }
.section--line { border-top: 1px solid var(--line); }

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(12px, 1.6vw, 20px);
}

@media (max-width: 720px) {
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
}

/* ---------- 5. 排版组件 ---------- */
.display-1,
.display-2,
.display-3 {
  font-family: var(--font-display);
  font-stretch: condensed;
  font-weight: 900;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.display-1 { font-size: clamp(34px, 7vw, 64px); line-height: 1.04; }
.display-2 { font-size: clamp(24px, 3.4vw, 34px); line-height: 1.18; }
.display-3 { font-size: 20px; line-height: 1.4; font-weight: 700; }

.lede {
  font-size: clamp(15px, 1.5vw, 17px);
  line-height: 1.9;
  color: var(--muted);
  max-width: 62ch;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 12px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--sand);
}

.eyebrow::before {
  content: "";
  width: 18px;
  height: 1px;
  flex: 0 0 auto;
  background: var(--gold);
}

.annot {
  font-size: 12px;
  letter-spacing: 0.3em;
  line-height: 1;
  color: var(--muted);
  writing-mode: vertical-rl;
  text-orientation: mixed;
}

.num,
.u-mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
}

.section-head {
  display: grid;
  gap: 10px;
  margin-bottom: clamp(22px, 3vw, 36px);
  max-width: 72ch;
}

.section-head__index {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.28em;
  color: var(--gold);
}

.section-head__title {
  font-family: var(--font-display);
  font-stretch: condensed;
  font-weight: 900;
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1.2;
  color: var(--ink);
}

.section-head__note {
  font-size: 15px;
  color: var(--muted);
}

/* ---------- 6. Bento 信息板 ---------- */
.bento {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(12px, 1.6vw, 20px);
}

.bento__cell { grid-column: span 12; min-width: 0; }

@media (min-width: 720px) {
  .bento__cell { grid-column: span 6; }
  .bento__cell--wide { grid-column: span 8; }
  .bento__cell--narrow { grid-column: span 4; }
  .bento__cell--full { grid-column: span 12; }
}

/* 档案卡 */
.cell {
  position: relative;
  height: 100%;
  padding: clamp(18px, 2.2vw, 26px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(29, 33, 39, 0.94), rgba(20, 23, 28, 0.94));
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.025), 0 14px 34px -28px rgba(0, 0, 0, 0.95);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.cell:hover {
  border-color: rgba(201, 162, 39, 0.45);
  transform: translateY(-2px);
}

.cell--focus { border-color: rgba(201, 162, 39, 0.55); }

.cell--focus::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius);
  pointer-events: none;
  background: radial-gradient(120% 92% at 100% 0%, rgba(99, 245, 210, 0.09), transparent 62%);
}

.cell__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 8px 14px;
  margin-bottom: 12px;
}

.cell__title { font-size: 20px; font-weight: 700; letter-spacing: 0.02em; color: var(--ink); }

.cell__meta {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.cell__body { font-size: 15px; color: var(--muted); }

.cell__foot {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
}

/* ---------- 7. 标签 / 数字 / 进度 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 12px;
  letter-spacing: 0.12em;
  line-height: 1.6;
  color: var(--muted);
}

.tag--gold { color: var(--sand); border-color: rgba(201, 162, 39, 0.5); background: rgba(201, 162, 39, 0.08); }
.tag--umber { color: var(--sand); background: var(--umber); border-color: transparent; }
.tag--cyan { color: var(--cyan); border-color: rgba(99, 245, 210, 0.4); background: rgba(99, 245, 210, 0.08); }

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

.stat__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 700;
  line-height: 1;
  color: var(--cyan);
}

.stat__label { font-size: 12px; letter-spacing: 0.16em; color: var(--muted); }

.stat-row {
  display: grid;
  gap: clamp(14px, 2vw, 24px);
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
}

.meter { height: 4px; border-radius: 2px; background: var(--line); overflow: hidden; }

.meter__bar {
  display: block;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--gold), var(--cyan));
  transition: width 700ms var(--ease);
}

/* ---------- 8. 纵向时间轴 ---------- */
.timeline { position: relative; padding-left: 26px; }

.timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--line);
}

.timeline__item { position: relative; padding-bottom: 26px; }
.timeline__item:last-child { padding-bottom: 0; }

.timeline__node {
  position: absolute;
  left: -26px;
  top: 7px;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  border: 1px solid var(--gold);
  background: var(--night);
  transition: background-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}

.timeline__item[data-active] .timeline__node {
  background: var(--cyan);
  border-color: var(--cyan);
  box-shadow: 0 0 0 4px rgba(99, 245, 210, 0.14);
}

.timeline__time {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--sand);
}

.timeline__body { margin-top: 6px; font-size: 15px; color: var(--muted); }

/* ---------- 9. 可展开内容组 ---------- */
.disclosure {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(20, 23, 28, 0.72);
  overflow: hidden;
}

.disclosure + .disclosure { margin-top: 10px; }

.disclosure__trigger {
  display: flex;
  width: 100%;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 18px;
  text-align: left;
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
  transition: color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.disclosure__trigger:hover { color: var(--sand); background: rgba(201, 162, 39, 0.06); }

.disclosure__trigger::after {
  content: "";
  flex: 0 0 auto;
  width: 9px;
  height: 9px;
  margin-right: 3px;
  border-right: 1px solid var(--gold);
  border-bottom: 1px solid var(--gold);
  transform: rotate(45deg);
  transition: transform var(--dur) var(--ease);
}

.disclosure__trigger[aria-expanded="true"] { color: var(--sand); }
.disclosure__trigger[aria-expanded="true"]::after { transform: rotate(-135deg); }

.disclosure__panel {
  padding: 14px 18px 18px;
  border-top: 1px solid var(--line);
  font-size: 15px;
  color: var(--muted);
}

.disclosure__panel[data-open] { animation: panelIn 240ms var(--ease); }

@keyframes panelIn {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: none; }
}

/* ---------- 10. 筛选标签 ---------- */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 13px;
  color: var(--muted);
  background: rgba(20, 23, 28, 0.6);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.chip:hover { color: var(--ink); border-color: rgba(201, 162, 39, 0.5); }

.chip[aria-pressed="true"] {
  color: var(--sand);
  border-color: var(--gold);
  background: rgba(201, 162, 39, 0.12);
}

.chip[aria-pressed="true"]::before {
  content: "";
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--cyan);
}

/* ---------- 11. 面包屑 ---------- */
.breadcrumbs {
  padding-block: 16px;
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.breadcrumbs ol { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }

.breadcrumbs li + li::before {
  content: "/";
  margin-right: 8px;
  color: #3A4048;
}

.breadcrumbs a { color: var(--muted); transition: color var(--dur) var(--ease); }
.breadcrumbs a:hover { color: var(--sand); }
.breadcrumbs [aria-current="page"] { color: var(--sand); }

/* ---------- 12. 图片容器 ---------- */
.media {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(150deg, #14171C 0%, #0B0D10 62%);
}

.media::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: repeating-linear-gradient(135deg, rgba(201, 162, 39, 0.07) 0 1px, transparent 1px 14px);
}

.media__frame {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

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

.media__caption {
  position: relative;
  padding: 10px 14px;
  border-top: 1px solid var(--line);
  background: rgba(11, 13, 16, 0.55);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

/* ---------- 13. 横向数据带 ---------- */
.scroller {
  position: relative;
  overflow: hidden;
  border-block: 1px solid var(--line);
  background: rgba(20, 23, 28, 0.5);
}

.scroller__track {
  display: flex;
  align-items: center;
  width: max-content;
  animation: scrollX 52s linear infinite;
}

.scroller:hover .scroller__track,
.scroller:focus-within .scroller__track { animation-play-state: paused; }

@keyframes scrollX {
  from { transform: translateX(0); }
  to { transform: translateX(-50%); }
}

/* ---------- 14. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 14px;
  letter-spacing: 0.08em;
  line-height: 1.4;
  color: var(--ink);
  background: transparent;
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.btn--ghost {
  color: var(--sand);
  border-color: rgba(201, 162, 39, 0.55);
  background: rgba(201, 162, 39, 0.06);
}

.btn--ghost:hover {
  color: #FFFFFF;
  border-color: var(--gold);
  background: rgba(201, 162, 39, 0.16);
}

.btn--solid {
  color: #16120A;
  font-weight: 700;
  border-color: var(--gold);
  background: var(--gold);
}

.btn--solid:hover { background: var(--sand); border-color: var(--sand); }

.btn--quiet { color: var(--muted); border-color: transparent; }
.btn--quiet:hover { color: var(--sand); border-color: var(--line); }

.copy-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--sand);
  background: rgba(201, 162, 39, 0.06);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.copy-btn:hover { border-color: var(--gold); background: rgba(201, 162, 39, 0.16); }

.copy-btn[data-copied] {
  color: var(--cyan);
  border-color: var(--cyan);
  background: rgba(99, 245, 210, 0.1);
}

.copy-btn__state { font-size: 12px; letter-spacing: 0.06em; color: var(--cyan); min-height: 1em; }

/* ---------- 15. 头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  background-color: transparent;
  border-bottom: 1px solid transparent;
  transition: background-color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}

.site-header[data-scrolled] {
  background-color: rgba(11, 13, 16, 0.94);
  border-bottom-color: var(--line);
  -webkit-backdrop-filter: blur(12px) saturate(120%);
  backdrop-filter: blur(12px) saturate(120%);
}

.skip-link {
  position: absolute;
  left: var(--gutter);
  top: -80px;
  z-index: 120;
  padding: 10px 16px;
  border: 1px solid var(--gold);
  border-radius: var(--radius);
  background: var(--slate);
  color: var(--sand);
  font-size: 14px;
  letter-spacing: 0.06em;
  transition: top 160ms var(--ease);
}

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

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: var(--header-h);
}

.brand { min-width: 0; }

.brand__link { display: flex; align-items: center; gap: 12px; }

.brand__mark {
  position: relative;
  flex: 0 0 auto;
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border: 1px solid var(--gold);
  border-radius: var(--radius);
  background: linear-gradient(160deg, rgba(201, 162, 39, 0.2), rgba(11, 13, 16, 0.7));
  font-family: var(--font-mono);
  font-size: 19px;
  font-weight: 700;
  color: var(--sand);
}

.brand__mark::after {
  content: "";
  position: absolute;
  right: -3px;
  bottom: -3px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 3px rgba(99, 245, 210, 0.14);
}

.brand__text { display: flex; flex-direction: column; gap: 2px; line-height: 1.15; min-width: 0; }

.brand__name {
  font-family: var(--font-display);
  font-stretch: condensed;
  font-weight: 900;
  font-size: 17px;
  letter-spacing: 0.06em;
  color: var(--ink);
}

.brand__tag { font-size: 12px; letter-spacing: 0.04em; color: var(--muted); }

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

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

.site-nav__list a {
  position: relative;
  display: inline-block;
  padding: 10px 12px;
  border-radius: var(--radius);
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--ink);
  transition: color var(--dur) var(--ease), background-color var(--dur) var(--ease);
}

.site-nav__list a::after {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: 4px;
  height: 1px;
  background: var(--gold);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur) var(--ease);
}

.site-nav__list a::before {
  content: "";
  position: absolute;
  left: 50%;
  top: 3px;
  width: 4px;
  height: 4px;
  margin-left: -2px;
  border-radius: 50%;
  background: var(--cyan);
  opacity: 0;
  transition: opacity var(--dur) var(--ease);
}

.site-nav__list a:hover { color: var(--sand); background-color: rgba(201, 162, 39, 0.07); }
.site-nav__list a:hover::after { transform: scaleX(1); }

.site-nav__list a[aria-current="page"] {
  color: var(--sand);
  background-color: rgba(201, 162, 39, 0.1);
}

.site-nav__list a[aria-current="page"]::after { transform: scaleX(1); }
.site-nav__list a[aria-current="page"]::before { opacity: 1; }

.site-nav__cta { margin-left: 6px; }

.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
  background: rgba(20, 23, 28, 0.65);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.nav-toggle:hover { border-color: rgba(201, 162, 39, 0.55); }

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

.nav-toggle__bars span {
  display: block;
  height: 1px;
  background: var(--sand);
  transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) { transform: translateY(2.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) { transform: translateY(-2.5px) rotate(-45deg); }

.nav-toggle__label { font-size: 12px; letter-spacing: 0.16em; color: var(--muted); }

.header-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  display: block;
  height: 1px;
  overflow: hidden;
}

.header-progress__bar {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: left center;
  background: linear-gradient(90deg, var(--gold) 0%, var(--sand) 46%, var(--cyan) 100%);
  transition: transform 90ms linear;
}

/* ---------- 16. 页脚 ---------- */
.site-footer {
  margin-top: clamp(48px, 8vw, 96px);
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(20, 23, 28, 0.72) 0%, var(--night) 66%);
  font-size: 14px;
  line-height: 1.8;
  color: var(--muted);
}

.footer-inner {
  display: grid;
  grid-template-columns: minmax(240px, 1fr) minmax(0, 2.6fr);
  gap: clamp(26px, 4vw, 56px);
  padding-block: clamp(40px, 6vw, 72px) clamp(26px, 4vw, 44px);
}

.footer-brand__name {
  font-family: var(--font-display);
  font-stretch: condensed;
  font-weight: 900;
  font-size: 22px;
  letter-spacing: 0.04em;
  color: var(--ink);
}

.footer-brand__tag {
  margin-top: 6px;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--sand);
}

.footer-brand__note { margin-top: 14px; max-width: 34ch; color: var(--muted); }

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: clamp(18px, 2.4vw, 28px);
}

.footer-col__title {
  position: relative;
  padding-top: 14px;
  margin-bottom: 12px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.2em;
  color: var(--sand);
}

.footer-col__title::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 22px;
  height: 1px;
  background: var(--gold);
}

.footer-col__list li + li { margin-top: 8px; }

.footer-col__list a {
  display: inline-block;
  color: var(--muted);
  transition: color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.footer-col__list a:hover { color: var(--sand); transform: translateX(3px); }

.footer-contact {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 24px;
  padding-block: 20px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.footer-contact__label {
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--sand);
}

.footer-contact__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 14px;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.footer-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 6px 22px;
  padding-block: 20px clamp(26px, 4vw, 40px);
  font-size: 12px;
  letter-spacing: 0.03em;
  color: var(--muted);
  border-bottom: 1px solid var(--line);
}

.footer-meta__legal { max-width: 46ch; }
.footer-meta__icp { font-family: var(--font-mono); color: var(--sand); }
.footer-meta__copy { font-family: var(--font-mono); }

/* ---------- 17. 显现动效 ---------- */
html.is-js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 480ms var(--ease), transform 480ms var(--ease);
}

html.is-js [data-reveal][data-revealed] {
  opacity: 1;
  transform: none;
}

/* ---------- 18. 工具类 ---------- */
.rule { height: 1px; margin: 0; border: 0; background: var(--line); }
.u-muted { color: var(--muted); }
.u-gold { color: var(--sand); }
.u-cyan { color: var(--cyan); }
.u-center { text-align: center; }

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- 19. 平板与手机 ---------- */
@media (max-width: 1024px) {
  .footer-inner { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-brand__note { max-width: 56ch; }
}

@media (max-width: 960px) {
  .brand__tag { display: none; }

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

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: block;
    padding: 8px var(--gutter) 20px;
    background-color: rgba(11, 13, 16, 0.98);
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
    -webkit-backdrop-filter: blur(14px);
    backdrop-filter: blur(14px);
    max-height: 0;
    opacity: 0;
    visibility: hidden;
    overflow: hidden;
    transition: max-height 320ms var(--ease), opacity 200ms var(--ease), visibility 0s linear 320ms;
  }

  .site-nav[data-open] {
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
    opacity: 1;
    visibility: visible;
    transition: max-height 380ms var(--ease), opacity 220ms var(--ease), visibility 0s;
  }

  .site-nav__list { display: block; }

  .site-nav__list li + li { border-top: 1px solid var(--line); }

  .site-nav__list a { display: block; padding: 14px 6px; font-size: 15px; }

  .site-nav__list a::before,
  .site-nav__list a::after { display: none; }

  .site-nav__list a[aria-current="page"] {
    color: var(--sand);
    padding-left: 16px;
    box-shadow: inset 2px 0 0 var(--gold);
  }

  .site-nav__cta { width: 100%; margin: 16px 0 0; }
}

@media (max-width: 620px) {
  .footer-grid { grid-template-columns: 1fr; }
  .footer-contact { gap: 8px 16px; }
  .footer-meta { justify-content: flex-start; }
}

/* ---------- 20. 降低动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  html.is-js [data-reveal] { opacity: 1; transform: none; }

  .scroller__track { animation: none; }
  .cell:hover { transform: none; }
  .footer-col__list a:hover { transform: none; }
}