/* =========================================================
   竞博体育 · /assets/site.css
   共享外壳：reset / tokens / 中文排版 / 头部 / 页脚 / 基础组件
   ========================================================= */

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

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

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd, ul, ol {
  margin: 0;
}

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

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

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

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

table { border-collapse: collapse; }

/* --- 2. Tokens ------------------------------------------ */
:root {
  --deep-navy: #08182E;
  --navy-layer: #102A4C;
  --blueprint-line: #1E3A5C;
  --deep-teal: #0E3B3F;
  --oxblood: #5A1F35;
  --indigo-deep: #23235E;
  --cyan-glow: #2FF3D6;
  --electric-orange: #FF7A2F;
  --pulse-amber: #FFC24B;
  --paper: #EEF4FA;
  --mist-text: #B9CBDE;
  --mint-signal: #5BE0A0;
  --ink: #0F2038;
  --ink-soft: #3A4E66;

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

  --shell-max: 1280px;
  --shell-narrow: 860px;
  --gutter: clamp(18px, 4vw, 56px);
  --radius-s: 12px;
  --radius-m: 16px;
  --radius-l: 20px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

/* --- 3. 中文排版基线 ------------------------------------ */
body {
  min-height: 100vh;
  background-color: var(--deep-navy);
  color: var(--paper);
  font-family: var(--font-sans);
  font-size: 18px;
  font-weight: 400;
  line-height: 1.9;
  letter-spacing: 0.01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 {
  font-weight: 900;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--paper);
}

h1 { font-size: clamp(32px, 4.6vw, 54px); }
h2 { font-size: clamp(26px, 3.2vw, 32px); font-weight: 700; letter-spacing: -0.02em; }
h3 { font-size: clamp(20px, 2vw, 24px); font-weight: 700; }
h4 { font-size: 18px; font-weight: 700; }

p { line-height: 1.9; }

strong { font-weight: 700; color: var(--paper); }

::selection {
  background-color: var(--cyan-glow);
  color: var(--deep-navy);
}

:focus-visible {
  outline: 2px solid var(--cyan-glow);
  outline-offset: 3px;
  border-radius: 4px;
}

/* --- 4. 跳转链接 ---------------------------------------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 300;
  padding: 10px 18px;
  border-radius: 999px;
  background-color: var(--cyan-glow);
  color: var(--deep-navy);
  font-size: 15px;
  font-weight: 700;
  line-height: 1.2;
  transform: translateY(-180%);
  transition: transform 200ms var(--ease);
}

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

/* --- 5. 头部 -------------------------------------------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 200;
  background-color: transparent;
  border-bottom: 1px solid transparent;
  transition: background-color 260ms var(--ease),
    border-color 260ms var(--ease),
    box-shadow 260ms var(--ease);
}

.site-header[data-scrolled="true"] {
  background-color: rgba(8, 24, 46, 0.95);
  border-bottom-color: var(--blueprint-line);
  box-shadow: 0 24px 48px -40px rgba(0, 0, 0, 0.95);
}

.header-shell {
  width: min(var(--shell-max), 100%);
  margin-inline: auto;
  padding: 20px var(--gutter);
  display: flex;
  align-items: center;
  gap: clamp(16px, 3vw, 40px);
  transition: padding 260ms var(--ease);
}

.site-header[data-scrolled="true"] .header-shell {
  padding-block: 10px;
}

.brand {
  flex: 0 0 auto;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.brand-index {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  line-height: 1.4;
  color: var(--cyan-glow);
}

.brand-name {
  font-size: clamp(19px, 2vw, 22px);
  font-weight: 900;
  letter-spacing: -0.01em;
  line-height: 1.2;
  color: var(--paper);
}

.brand-sub {
  font-size: 13px;
  font-weight: 400;
  line-height: 1.4;
  color: var(--mist-text);
  white-space: nowrap;
}

.site-nav {
  flex: 1 1 auto;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: clamp(10px, 1.6vw, 24px);
}

.nav-caption { display: none; }

.nav-list {
  display: flex;
  align-items: center;
  gap: clamp(6px, 1.2vw, 20px);
}

.nav-item { flex: 0 0 auto; }

.nav-link {
  display: inline-flex;
  align-items: baseline;
  gap: 5px;
  padding: 6px 4px;
  font-size: 15px;
  font-weight: 500;
  line-height: 1.5;
  color: var(--mist-text);
  border-bottom: 2px solid transparent;
  transition: color 180ms var(--ease), border-color 180ms var(--ease);
}

.nav-link:hover { color: var(--paper); }

.nav-link[aria-current="page"] {
  color: var(--cyan-glow);
  border-bottom-color: var(--cyan-glow);
}

.nav-num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  line-height: 1;
  color: var(--mist-text);
  opacity: 0.55;
  transition: color 180ms var(--ease);
}

.nav-link:hover .nav-num { color: var(--pulse-amber); opacity: 1; }
.nav-link[aria-current="page"] .nav-num { color: var(--cyan-glow); opacity: 1; }

.nav-note { display: none; }
.nav-cta { display: none; }

.header-tools {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 12px;
}

/* --- 6. 按钮 -------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 22px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-family: var(--font-sans);
  font-size: 15px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.01em;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color 200ms var(--ease), color 200ms var(--ease),
    border-color 200ms var(--ease), transform 200ms var(--ease);
}

.btn-cta {
  background-color: var(--cyan-glow);
  color: var(--deep-navy);
}

.btn-cta:hover { background-color: var(--paper); }

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

.btn-ghost:hover {
  border-color: var(--cyan-glow);
  color: var(--cyan-glow);
}

.btn-warn {
  background-color: var(--electric-orange);
  color: var(--deep-navy);
}

.btn-warn:hover { background-color: var(--pulse-amber); }

.btn-sm {
  padding: 9px 16px;
  font-size: 14px;
}

/* --- 7. 移动导航按钮与抽屉 ------------------------------ */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border: 1px solid var(--blueprint-line);
  border-radius: 999px;
  color: var(--paper);
  font-size: 14px;
  font-weight: 700;
  line-height: 1;
  transition: border-color 200ms var(--ease), color 200ms var(--ease);
}

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

.nav-toggle[aria-expanded="true"] {
  border-color: var(--cyan-glow);
  color: var(--cyan-glow);
}

.nav-toggle-label { letter-spacing: 0.02em; }

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

.nav-toggle-bars i {
  display: block;
  height: 2px;
  border-radius: 2px;
  background-color: currentColor;
  transition: transform 220ms var(--ease), opacity 220ms var(--ease);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bars i:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* --- 8. 滚动进度刻度 ------------------------------------ */
.scroll-meter {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  overflow: hidden;
  background-color: transparent;
  pointer-events: none;
}

.scroll-meter-fill {
  display: block;
  width: 100%;
  height: 100%;
  background-image: linear-gradient(90deg, var(--cyan-glow), var(--electric-orange));
  transform: scaleX(0);
  transform-origin: 0 50%;
  transition: transform 120ms linear;
}

/* --- 9. 头部断点：抽屉导航 ------------------------------ */
@media (max-width: 1024px) {
  .brand-sub { display: none; }
  .header-cta { display: none; }
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: auto;
    z-index: 210;
    width: min(360px, 88vw);
    display: flex;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 0;
    padding: 96px clamp(20px, 6vw, 32px) 40px;
    background-color: var(--deep-navy);
    background-image:
      linear-gradient(rgba(30, 58, 92, 0.55) 1px, transparent 1px),
      linear-gradient(90deg, rgba(30, 58, 92, 0.55) 1px, transparent 1px);
    background-size: 32px 32px;
    border-left: 1px solid var(--blueprint-line);
    box-shadow: -40px 0 80px -50px #000;
    overflow-y: auto;
    transform: translateX(102%);
    visibility: hidden;
    transition: transform 320ms var(--ease), visibility 320ms var(--ease);
  }

  .site-nav[data-open] {
    transform: translateX(0);
    visibility: visible;
  }

  .nav-caption {
    display: block;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--blueprint-line);
    font-family: var(--font-mono);
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    line-height: 1.6;
    color: var(--cyan-glow);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin-top: 6px;
  }

  .nav-item {
    border-bottom: 1px solid rgba(30, 58, 92, 0.7);
  }

  .nav-link {
    width: 100%;
    justify-content: flex-start;
    padding: 16px 0;
    font-size: 17px;
    font-weight: 700;
    border-bottom: 0;
  }

  .nav-num { font-size: 12px; opacity: 0.7; }

  .nav-note {
    display: block;
    margin-top: 22px;
    font-size: 14px;
    line-height: 1.75;
    color: var(--mist-text);
  }

  .nav-cta {
    display: inline-flex;
    width: 100%;
    margin-top: 18px;
  }

  body[data-nav-locked] { overflow: hidden; }
}

/* --- 10. 页脚 ------------------------------------------- */
.site-footer {
  position: relative;
  margin-top: clamp(64px, 9vw, 140px);
  background-color: var(--deep-navy);
  border-top: 1px solid var(--blueprint-line);
  color: var(--mist-text);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(30, 58, 92, 0.45) 1px, transparent 1px),
    linear-gradient(90deg, rgba(30, 58, 92, 0.45) 1px, transparent 1px);
  background-size: 56px 56px;
  -webkit-mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.6), transparent 72%);
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.6), transparent 72%);
  pointer-events: none;
}

.footer-shell {
  position: relative;
  width: min(var(--shell-max), 100%);
  margin-inline: auto;
  padding: clamp(44px, 6vw, 88px) var(--gutter) clamp(18px, 2.5vw, 28px);
  display: grid;
  grid-template-columns: minmax(240px, 1.4fr) repeat(3, minmax(130px, 0.7fr));
  gap: clamp(28px, 4vw, 56px);
}

.footer-brand {
  display: grid;
  gap: 8px;
  align-content: start;
}

.footer-index {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  line-height: 1.6;
  color: var(--cyan-glow);
}

.footer-brand-name {
  font-size: 26px;
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--paper);
}

.footer-brand-sub {
  font-size: 14px;
  line-height: 1.8;
  color: var(--mist-text);
}

.footer-brand-link {
  justify-self: start;
  margin-top: 6px;
  padding-bottom: 4px;
  border-bottom: 1px solid var(--blueprint-line);
  font-size: 15px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--paper);
  transition: color 180ms var(--ease), border-color 180ms var(--ease);
}

.footer-brand-link:hover {
  color: var(--cyan-glow);
  border-bottom-color: var(--cyan-glow);
}

.footer-col { display: block; }

.footer-col-title {
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  line-height: 1.6;
  color: var(--paper);
}

.footer-list {
  display: grid;
  gap: 10px;
}

.footer-list a {
  font-size: 15px;
  line-height: 1.7;
  color: var(--mist-text);
  transition: color 180ms var(--ease);
}

.footer-list a:hover { color: var(--cyan-glow); }

.footer-base {
  position: relative;
  width: min(var(--shell-max), 100%);
  margin-inline: auto;
  margin-top: clamp(24px, 4vw, 44px);
  padding: clamp(18px, 2.5vw, 26px) var(--gutter) clamp(28px, 4vw, 44px);
  border-top: 1px solid var(--blueprint-line);
  display: grid;
  gap: 10px;
}

.footer-contact {
  font-size: 15px;
  line-height: 1.8;
  color: var(--paper);
}

.footer-legal {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  line-height: 1.9;
  color: var(--mist-text);
}

@media (max-width: 1024px) {
  .footer-shell {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 640px) {
  .footer-shell {
    grid-template-columns: minmax(0, 1fr);
    gap: 32px;
  }
}

/* --- 11. 容器与网格 ------------------------------------- */
.container {
  width: min(var(--shell-max), 100%);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.container-narrow {
  width: min(var(--shell-narrow), 100%);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.prose { max-width: 68ch; }

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(16px, 2.2vw, 32px);
}

@media (max-width: 1024px) {
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .grid-12 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

/* --- 12. 章节与分区 ------------------------------------- */
.section { padding-block: clamp(48px, 7vw, 104px); }
.section--tight { padding-block: clamp(28px, 4vw, 56px); }

.zone-navy { background-color: var(--navy-layer); }
.zone-teal { background-color: var(--deep-teal); }
.zone-oxblood { background-color: var(--oxblood); }
.zone-indigo { background-color: var(--indigo-deep); }

.zone-paper {
  background-color: var(--paper);
  color: var(--ink);
}

.zone-paper h1,
.zone-paper h2,
.zone-paper h3,
.zone-paper h4,
.zone-paper strong { color: var(--ink); }

.zone-paper .section-lede,
.zone-paper .card-text,
.zone-paper .stat-label,
.zone-paper .figure-caption { color: var(--ink-soft); }

.blueprint {
  background-image:
    linear-gradient(rgba(30, 58, 92, 0.5) 1px, transparent 1px),
    linear-gradient(90deg, rgba(30, 58, 92, 0.5) 1px, transparent 1px);
  background-size: 48px 48px;
}

.section-head {
  display: grid;
  gap: 12px;
  margin-bottom: clamp(24px, 3vw, 44px);
}

.section-title {
  font-size: clamp(26px, 3.2vw, 32px);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.section-lede {
  max-width: 62ch;
  font-size: 18px;
  line-height: 1.9;
  color: var(--mist-text);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  line-height: 1.6;
  color: var(--cyan-glow);
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background-color: currentColor;
}

.index-num {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  line-height: 1.6;
  color: var(--cyan-glow);
}

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

/* --- 13. 面板与卡片 ------------------------------------- */
.panel {
  position: relative;
  padding: clamp(20px, 2.6vw, 32px);
  border: 1px solid var(--blueprint-line);
  border-radius: var(--radius-l);
  background-color: var(--navy-layer);
}

.panel--teal { background-color: var(--deep-teal); }
.panel--oxblood { background-color: var(--oxblood); }
.panel--indigo { background-color: var(--indigo-deep); }
.panel--flush { background-color: transparent; }

.card {
  display: grid;
  gap: 12px;
  align-content: start;
  padding: clamp(18px, 2.2vw, 26px);
  border: 1px solid var(--blueprint-line);
  border-radius: var(--radius-m);
  background-color: var(--navy-layer);
  transition: border-color 240ms var(--ease), transform 240ms var(--ease),
    background-color 240ms var(--ease);
}

.card:hover {
  border-color: rgba(47, 243, 214, 0.5);
  transform: translateY(-3px);
}

.card-title {
  font-size: 20px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--paper);
}

.card-text {
  font-size: 16px;
  line-height: 1.85;
  color: var(--mist-text);
}

/* --- 14. 标签与数据锚点 --------------------------------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border: 1px solid var(--blueprint-line);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  line-height: 1.6;
  color: var(--mist-text);
}

.tag--cyan { border-color: var(--cyan-glow); color: var(--cyan-glow); }
.tag--orange { border-color: var(--electric-orange); color: var(--electric-orange); }
.tag--amber { border-color: var(--pulse-amber); color: var(--pulse-amber); }

.stat {
  display: grid;
  gap: 4px;
}

.stat-value {
  font-family: var(--font-mono);
  font-size: clamp(32px, 4vw, 48px);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.05;
  color: var(--cyan-glow);
}

.stat-label {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  line-height: 1.6;
  color: var(--mist-text);
}

.stat--amber .stat-value { color: var(--pulse-amber); }
.stat--orange .stat-value { color: var(--electric-orange); }
.stat--mint .stat-value { color: var(--mint-signal); }

.pulse {
  animation: jb-pulse 2400ms var(--ease) 1;
}

@keyframes jb-pulse {
  0% { text-shadow: 0 0 0 rgba(47, 243, 214, 0); }
  35% { text-shadow: 0 0 20px rgba(47, 243, 214, 0.75); }
  100% { text-shadow: 0 0 0 rgba(47, 243, 214, 0); }
}

/* --- 15. 面包屑与数据表 --------------------------------- */
.breadcrumbs { padding-block: clamp(14px, 2vw, 22px); }

.breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  line-height: 1.7;
  color: var(--mist-text);
}

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

.breadcrumbs a {
  color: var(--mist-text);
  transition: color 160ms var(--ease);
}

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

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

.data-table {
  width: 100%;
  border: 1px solid var(--blueprint-line);
  border-radius: var(--radius-s);
  overflow: hidden;
  font-size: 15px;
}

.data-table th,
.data-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--blueprint-line);
  line-height: 1.7;
}

.data-table th {
  background-color: var(--navy-layer);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--mist-text);
}

.data-table td { color: var(--paper); }
.data-table tbody tr:last-child td { border-bottom: 0; }

.data-table .num {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--cyan-glow);
}

/* --- 16. 图片容器（供页面阶段放置图像） ------------------ */
.figure {
  margin: 0;
  display: grid;
  gap: 10px;
}

.figure-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--blueprint-line);
  border-radius: var(--radius-l);
  background-color: var(--navy-layer);
}

.figure-frame > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.figure-frame--wide { aspect-ratio: 16 / 9; }
.figure-frame--plan { aspect-ratio: 4 / 3; }
.figure-frame--tall { aspect-ratio: 4 / 5; }
.figure-frame--square { aspect-ratio: 1 / 1; }

.figure-frame--empty {
  background-image: linear-gradient(
    135deg,
    rgba(30, 58, 92, 0.9) 25%,
    transparent 25%,
    transparent 50%,
    rgba(30, 58, 92, 0.9) 50%,
    rgba(30, 58, 92, 0.9) 75%,
    transparent 75%
  );
  background-size: 14px 14px;
}

.figure-caption {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
  line-height: 1.7;
  color: var(--mist-text);
}

/* --- 17. 显现动效 --------------------------------------- */
.js-ready [data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 420ms var(--ease), transform 420ms var(--ease);
}

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

/* --- 18. 无障碍隐藏 ------------------------------------- */
.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* --- 19. 减少动态效果 ----------------------------------- */
@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;
  }

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

  .card:hover { transform: none; }
}