/* =========================================================
   亿博体育 YIBO — /assets/site.css
   夜间赛场控制台 · 侧边轨道导航 · 斜向网格
   ========================================================= */

/* ---------- 0. 设计变量 ---------- */
:root {
  --ink: #0A0E0D;
  --panel: #0F2A24;
  --card: #16211F;
  --line: #2B3B37;
  --line-soft: rgba(43, 59, 55, 0.62);

  --cyan: #35F2D0;
  --cyan-06: rgba(53, 242, 208, 0.06);
  --cyan-10: rgba(53, 242, 208, 0.10);
  --cyan-28: rgba(53, 242, 208, 0.28);
  --cyan-45: rgba(53, 242, 208, 0.45);

  --orange: #FF6A2B;
  --orange-soft: #FFA07A;
  --orange-10: rgba(255, 106, 43, 0.10);
  --orange-32: rgba(255, 106, 43, 0.32);

  --gold: #E8C86A;
  --silver: #C9D3D8;
  --bronze: #C98A5A;

  --text: #F3F8F6;
  --text-soft: #CFE0DA;
  --muted: #9FB3AC;

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

  --rail-w: 0px;
  --topbar-h: 60px;
  --edge: 20px;
  --radius: 2px;
  --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
  --shadow-card: 0 16px 36px -20px rgba(0, 0, 0, 0.92);
}

@media (min-width: 768px) {
  :root { --edge: 32px; }
}

@media (min-width: 1024px) {
  :root {
    --rail-w: 88px;
    --topbar-h: 64px;
  }
}

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

* { margin: 0; }

ul[class],
ol[class] {
  list-style: none;
  padding: 0;
}

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

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

a { color: inherit; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--topbar-h) + 20px);
}

body {
  min-height: 100vh;
  padding-top: var(--topbar-h);
  padding-left: var(--rail-w);
  background: var(--ink);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body.nav-open { overflow: hidden; }

/* ---------- 2. 焦点与可访问性 ---------- */
a:focus-visible,
button:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 2px;
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* ---------- 3. 基础排版 ---------- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.06;
  color: var(--text);
}

h1 { font-size: clamp(2.6rem, 7vw, 5.5rem); }
h2 { font-size: clamp(1.75rem, 3.6vw, 2.75rem); }
h3 { font-size: clamp(1.2rem, 2vw, 1.55rem); line-height: 1.2; }

p { color: inherit; }

.lead {
  max-width: 60ch;
  font-size: clamp(1rem, 1.3vw, 1.14rem);
  line-height: 1.82;
  color: var(--text-soft);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
}

.eyebrow::before {
  content: "";
  width: 18px;
  height: 1px;
  background: currentColor;
  flex: 0 0 auto;
}

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

.prose {
  max-width: 68ch;
  color: var(--text-soft);
}

.prose > * + * { margin-top: 1.05em; }

.prose p { line-height: 1.85; }

.prose h2,
.prose h3 { margin-top: 1.9em; color: var(--text); }

.prose ul,
.prose ol {
  padding-left: 1.3em;
  list-style: disc;
}

.prose ol { list-style: decimal; }

.prose li + li { margin-top: 0.4em; }

.prose a {
  color: var(--cyan);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

.prose strong { color: var(--text); font-weight: 700; }

/* ---------- 4. 布局工具 ---------- */
.container {
  width: 100%;
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: var(--edge);
}

.section { position: relative; }

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 14px;
  padding-bottom: 14px;
  margin-bottom: 28px;
  border-bottom: 1px solid var(--line);
}

.section-head__title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3vw, 2.1rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.05;
}

.section-head__meta {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}

.grid {
  display: grid;
  gap: var(--gap, 20px);
  grid-template-columns: repeat(auto-fit, minmax(min(260px, 100%), 1fr));
}

.grid--2 { grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(min(216px, 100%), 1fr)); }

.stack {
  display: flex;
  flex-direction: column;
  gap: var(--gap, 20px);
}

.rule {
  height: 1px;
  border: 0;
  margin: 32px 0;
  background: var(--line);
}

/* ---------- 5. 面包屑 ---------- */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-bottom: 20px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.breadcrumbs a {
  color: var(--muted);
  text-decoration: none;
  transition: color 0.16s var(--ease);
}

.breadcrumbs a:hover { color: var(--cyan); }

.breadcrumbs li + li::before {
  content: "/";
  margin-right: 8px;
  color: var(--line);
}

.breadcrumbs [aria-current="page"] { color: var(--text); }

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 20px;
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.04em;
  line-height: 1.2;
  text-align: center;
  text-decoration: none;
  color: var(--text);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.18s var(--ease), border-color 0.18s var(--ease),
              color 0.18s var(--ease), transform 0.18s var(--ease);
}

.btn:hover {
  border-color: var(--cyan-45);
  background: #1B2926;
}

.btn:active { transform: translateY(1px); }

.btn--accent {
  color: #14070C;
  background: linear-gradient(135deg, var(--orange), #E2521A);
  border-color: transparent;
}

.btn--accent:hover {
  color: #14070C;
  background: linear-gradient(135deg, var(--orange-soft), var(--orange));
  border-color: transparent;
}

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

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

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

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--cyan);
  text-decoration: none;
}

.link-arrow::after {
  content: "\2192";
  transition: transform 0.18s var(--ease);
}

.link-arrow:hover::after { transform: translateX(4px); }

/* ---------- 7. 标签与数据 ---------- */
.tag {
  display: inline-block;
  padding: 3px 9px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 500;
  letter-spacing: 0.14em;
  line-height: 1.5;
  text-transform: uppercase;
  color: var(--cyan);
  background: var(--cyan-10);
  border: 1px solid var(--cyan-28);
  border-radius: var(--radius);
}

.tag--accent {
  color: var(--orange);
  background: var(--orange-10);
  border-color: var(--orange-32);
}

.tag--mute {
  color: var(--muted);
  background: rgba(159, 179, 172, 0.06);
  border-color: var(--line);
}

.tag--slant {
  clip-path: polygon(9px 0, 100% 0, 100% 100%, 0 100%, 0 9px);
}

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

.metric__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  font-weight: 600;
  line-height: 1;
  color: var(--cyan);
}

.metric__label {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}

.metric__grid {
  display: grid;
  gap: 18px;
  grid-template-columns: repeat(auto-fit, minmax(min(120px, 100%), 1fr));
}

/* ---------- 8. 卡片 ---------- */
.card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
}

/* ---------- 9. 图片容器基础规则 ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background-color: #0B1614;
  background-image:
    repeating-linear-gradient(105deg, var(--cyan-06) 0 1px, transparent 1px 46px),
    radial-gradient(120% 120% at 18% 0%, rgba(53, 242, 208, 0.12), transparent 62%),
    linear-gradient(160deg, var(--panel), var(--ink));
}

.media > img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, transparent 46%, rgba(6, 10, 9, 0.55) 100%);
}

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

.media__tag {
  position: absolute;
  left: 12px;
  bottom: 12px;
  z-index: 2;
}

/* ---------- 10. 显现动效 ---------- */
.js-on [data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.5s var(--ease), transform 0.5s var(--ease);
}

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

/* ---------- 11. 跳过链接 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 200;
  padding: 10px 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: #05201B;
  background: var(--cyan);
  border-radius: var(--radius);
  text-decoration: none;
  transform: translateY(-180%);
  transition: transform 0.18s var(--ease);
}

.skip-link:focus,
.skip-link:focus-visible {
  transform: translateY(0);
  outline-offset: 3px;
}

/* ---------- 12. 顶栏 ---------- */
.site-header {
  position: relative;
  z-index: 50;
}

.topbar {
  position: fixed;
  top: 0;
  left: var(--rail-w);
  right: 0;
  z-index: 90;
  height: var(--topbar-h);
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 var(--edge);
  background: rgba(10, 14, 13, 0.88);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  color: var(--text);
  text-decoration: none;
}

.brand__mark {
  position: relative;
  display: block;
  width: 30px;
  height: 30px;
  background: linear-gradient(135deg, var(--cyan), #12B79B);
  clip-path: polygon(0 0, 100% 0, 100% 62%, 62% 100%, 0 100%);
}

.brand__mark::after {
  content: "";
  position: absolute;
  inset: 7px;
  background: var(--ink);
  clip-path: polygon(0 0, 100% 0, 100% 62%, 62% 100%, 0 100%);
}

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1;
}

.brand__cn {
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--text);
  white-space: nowrap;
}

.brand__en {
  margin-top: 4px;
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.3em;
  color: var(--cyan);
}

.topbar__tri {
  display: flex;
  align-items: center;
  gap: 4px;
  flex: 1 1 0;
  min-width: 0;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scrollbar-width: none;
}

.topbar__tri::-webkit-scrollbar { display: none; }

.tri-link {
  flex: 0 0 auto;
  padding: 6px 11px;
  font-size: 12.5px;
  letter-spacing: 0.04em;
  white-space: nowrap;
  color: var(--muted);
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: 999px;
  transition: color 0.18s var(--ease), background 0.18s var(--ease),
              border-color 0.18s var(--ease);
}

.tri-link:hover,
.tri-link:focus-visible {
  color: var(--cyan);
  background: var(--cyan-06);
  border-color: var(--cyan-28);
}

.topbar__tools {
  display: none;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
}

@media (min-width: 900px) {
  .topbar__tools { display: flex; }
}

.ver-chip {
  padding: 3px 7px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  color: var(--muted);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.topbar__mail {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--muted);
  white-space: nowrap;
}

@media (max-width: 1279px) {
  .topbar__mail { display: none; }
}

.nav-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 auto;
  width: 42px;
  height: 42px;
  padding: 0;
  color: var(--text);
  background: transparent;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  cursor: pointer;
  transition: border-color 0.18s var(--ease), background 0.18s var(--ease);
}

.nav-toggle:hover {
  border-color: var(--cyan-45);
  background: var(--cyan-06);
}

.nav-toggle__bars {
  display: flex;
  flex-direction: column;
  gap: 4px;
  width: 16px;
}

.nav-toggle__bars span {
  display: block;
  height: 2px;
  width: 100%;
  background: currentColor;
  transition: transform 0.22s var(--ease), opacity 0.18s var(--ease);
}

.site-header[data-open] .nav-toggle__bars span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.site-header[data-open] .nav-toggle__bars span:nth-child(2) { opacity: 0; }

.site-header[data-open] .nav-toggle__bars span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

@media (min-width: 1024px) {
  .nav-toggle { display: none; }
}

/* ---------- 13. 遮罩 ---------- */
.nav-scrim {
  position: fixed;
  top: var(--topbar-h);
  right: 0;
  bottom: 0;
  left: 0;
  z-index: 84;
  background: rgba(6, 10, 9, 0.74);
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.24s var(--ease);
}

.site-header[data-open] .nav-scrim {
  opacity: 1;
  pointer-events: auto;
}

@media (min-width: 1024px) {
  .nav-scrim { display: none; }
}

/* ---------- 14. 侧边轨道导航 ---------- */
.rail {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  z-index: 85;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
  width: 88px;
  padding: calc(var(--topbar-h) + 16px) 0 22px;
  background: linear-gradient(180deg, #0A1210 0%, var(--panel) 55%, #0A1210 100%);
  border-right: 1px solid var(--line);
  overflow-y: auto;
  overscroll-behavior: contain;
  scrollbar-width: thin;
  transform: translateX(-105%);
  transition: transform 0.28s var(--ease);
}

.rail::-webkit-scrollbar { width: 3px; }
.rail::-webkit-scrollbar-thumb {
  background: var(--line);
  border-radius: 2px;
}

.site-header[data-open] .rail { transform: none; }

.rail__list {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  margin: 0;
  padding: 0;
}

.rail-link {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  width: 56px;
  min-height: 54px;
  padding: 10px 0;
  color: var(--muted);
  text-decoration: none;
  font-size: 12px;
  line-height: 1;
  border: 1px solid transparent;
  border-radius: var(--radius);
  transition: color 0.18s var(--ease), background 0.18s var(--ease),
              border-color 0.18s var(--ease);
}

.rail-link__no {
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.1em;
  color: var(--muted);
  opacity: 0.72;
}

.rail-link__text {
  writing-mode: vertical-rl;
  text-orientation: upright;
  letter-spacing: 0.16em;
  font-size: 12px;
}

.rail-link:hover {
  color: var(--text);
  background: var(--cyan-06);
  border-color: var(--line);
}

.rail-link:hover .rail-link__no { opacity: 1; }

.rail-link[aria-current="page"] {
  color: var(--cyan);
  background: rgba(53, 242, 208, 0.09);
  border-color: var(--cyan-28);
}

.rail-link[aria-current="page"] .rail-link__no {
  color: var(--cyan);
  opacity: 1;
}

.rail-link[aria-current="page"]::before {
  content: "";
  position: absolute;
  top: 50%;
  left: -16px;
  width: 3px;
  height: 26px;
  border-radius: 0 2px 2px 0;
  background: var(--cyan);
  transform: translateY(-50%);
  box-shadow: 0 0 12px rgba(53, 242, 208, 0.55);
}

.rail__foot {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  margin-top: auto;
  padding-top: 14px;
}

.rail__line {
  width: 1px;
  height: 34px;
  background: linear-gradient(180deg, transparent, var(--line), transparent);
}

.rail__dot {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 10px rgba(53, 242, 208, 0.7);
}

@media (min-width: 1024px) {
  .rail { transform: none; }
}

@media (max-width: 1023px) {
  .rail {
    top: var(--topbar-h);
    width: min(304px, 86vw);
    align-items: stretch;
    padding: 18px 16px 22px;
    background: linear-gradient(180deg, #0C1715 0%, #0B1412 100%);
    box-shadow: 30px 0 70px -32px rgba(0, 0, 0, 0.95);
  }

  .rail__list {
    align-items: stretch;
    gap: 2px;
  }

  .rail-link {
    flex-direction: row;
    align-items: center;
    justify-content: flex-start;
    gap: 12px;
    width: 100%;
    min-height: 50px;
    padding: 0 14px 0 18px;
    font-size: 15.5px;
    border-radius: var(--radius);
  }

  .rail-link__text {
    writing-mode: horizontal-tb;
    text-orientation: mixed;
    letter-spacing: 0.06em;
    font-size: 15.5px;
    font-family: var(--font-display);
    font-weight: 700;
  }

  .rail-link__no {
    font-size: 10px;
    letter-spacing: 0.12em;
  }

  .rail-link[aria-current="page"]::before {
    left: 6px;
    width: 3px;
    height: 22px;
    border-radius: 2px;
  }

  .rail__foot { display: none; }
}

/* ---------- 15. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: 72px;
  padding: 48px 0 26px;
  background: linear-gradient(180deg, var(--ink) 0%, #0C1614 42%, var(--panel) 100%);
  border-top: 1px solid var(--line);
  color: var(--muted);
}

.footer__inner {
  display: grid;
  gap: 36px;
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: var(--edge);
}

@media (min-width: 900px) {
  .footer__inner {
    grid-template-columns: minmax(0, 1.05fr) minmax(0, 1.4fr);
    gap: 52px;
  }
}

.footer__brand { min-width: 0; }

.footer__brandline {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 1.3;
  color: var(--text);
}

.footer__note {
  max-width: 36ch;
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.72;
  color: var(--muted);
}

.footer__contact {
  display: grid;
  gap: 8px;
  margin-top: 22px;
}

.footer__contact p {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px;
  min-width: 0;
}

.footer__label {
  flex: 0 0 auto;
  min-width: 56px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
}

.footer__value {
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.01em;
  color: var(--text-soft);
  word-break: break-word;
}

.footer__cols {
  display: grid;
  gap: 28px;
  grid-template-columns: repeat(auto-fit, minmax(min(140px, 100%), 1fr));
}

.footer__col { min-width: 0; }

.footer__title {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--cyan);
}

.footer__list {
  display: grid;
  gap: 9px;
  margin-top: 14px;
  list-style: none;
  padding: 0;
}

.footer__list a {
  position: relative;
  display: inline-block;
  font-size: 14px;
  color: var(--muted);
  text-decoration: none;
  transition: color 0.16s var(--ease);
}

.footer__list a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 0;
  height: 1px;
  background: var(--cyan);
  transition: width 0.2s var(--ease);
}

.footer__list a:hover,
.footer__list a:focus-visible { color: var(--text); }

.footer__list a:hover::after,
.footer__list a:focus-visible::after { width: 100%; }

.footer__legal {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 24px;
  max-width: 1200px;
  margin: 36px auto 0;
  padding: 18px var(--edge) 0;
  border-top: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--muted);
}

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

/* ---------- 16. 返回顶部 ---------- */
.to-top {
  position: fixed;
  right: 18px;
  bottom: 18px;
  z-index: 70;
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  padding: 0;
  color: var(--cyan);
  background: rgba(12, 22, 20, 0.92);
  border: 1px solid var(--line);
  border-radius: 50%;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity 0.2s var(--ease), transform 0.2s var(--ease),
              visibility 0.2s var(--ease), border-color 0.2s var(--ease);
}

.to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.to-top:hover {
  border-color: var(--cyan-45);
  background: rgba(18, 32, 29, 0.96);
}

.to-top svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}

.to-top__ring {
  fill: none;
  stroke: var(--line);
  stroke-width: 2;
}

.to-top__bar {
  fill: none;
  stroke: var(--orange);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-dasharray: 119.38;
  stroke-dashoffset: 119.38;
  transition: stroke-dashoffset 0.1s linear;
}

.to-top__arrow {
  width: 0;
  height: 0;
  border-left: 5px solid transparent;
  border-right: 5px solid transparent;
  border-bottom: 7px solid currentColor;
  transform: translateY(-1px);
}

@media (min-width: 1024px) {
  .to-top {
    right: 30px;
    bottom: 30px;
  }
}

/* ---------- 17. 减弱动效 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  .js-on [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .rail,
  .nav-scrim,
  .to-top { transition: none; }
}

/* ---------- 18. 打印 ---------- */
@media print {
  .topbar,
  .rail,
  .nav-scrim,
  .to-top,
  .skip-link { display: none !important; }

  body {
    padding: 0;
    background: #FFFFFF;
    color: #111111;
  }
}