/* ==========================================================================
   /assets/site.css — 易倍体育EMC 共享外壳与通用组件
   设计骨架：双语并排战术板 · 斜切色块 · 1px 精密网格 · 直角与等宽数字
   ========================================================================== */

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

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

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

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

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

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

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

table { border-collapse: collapse; width: 100%; }

/* 2. Tokens --------------------------------------------------------------- */
:root {
  --navy: #0B2A6F;
  --blue: #1B4FD8;
  --pulse: #4C7BFF;
  --ice: #EEF3FF;
  --shell: #F4F7FF;
  --orange: #FF6A2B;
  --green: #12B886;
  --graphite: #12161F;
  --gray: #6B7688;
  --line: #C9D6F0;
  --white: #FFFFFF;

  --gutter: clamp(16px, 4vw, 48px);
  --gap: clamp(20px, 2.6vw, 36px);
  --radius: 2px;
  --seam: 2.6vw;

  --font-body: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-narrow: "Arial Narrow", "Helvetica Neue Condensed", "Roboto Condensed", "PingFang SC", Arial, sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", "Cascadia Mono", Consolas, "Liberation Mono", monospace;
  --font-serif: Georgia, "Songti SC", "Times New Roman", serif;
}

/* 3. 基础排印 -------------------------------------------------------------- */
body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  color: var(--graphite);
  background-color: var(--shell);
  background-image: linear-gradient(90deg, rgba(201, 214, 240, .3) 1px, transparent 1px);
  background-size: 96px 100%;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-weight: 800;
  line-height: 1.16;
  letter-spacing: -.01em;
  color: var(--navy);
}

strong { font-weight: 700; }

.num {
  font-family: var(--font-mono);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  letter-spacing: -.01em;
}

.u-en {
  font-family: var(--font-narrow);
  text-transform: uppercase;
  letter-spacing: .12em;
}

#main-content { display: block; scroll-margin-top: 130px; }

/* 聚焦可见 */
:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: 3px;
}

/* 4. Skip link ------------------------------------------------------------ */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 200;
  padding: 12px 18px;
  background: var(--navy);
  color: var(--white);
  font-size: 14px;
  font-weight: 700;
  border-radius: var(--radius);
  border-left: 3px solid var(--orange);
  transform: translateY(-160%);
  transition: transform .2s ease;
}
.skip-link:focus,
.skip-link:focus-visible { transform: translateY(0); }

/* 5. 页头：悬浮胶囊浮岛 ---------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  padding: 14px 0 10px;
  background: rgba(244, 247, 255, .84);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  backdrop-filter: blur(16px) saturate(150%);
  border-bottom: 1px solid transparent;
  transition: padding .28s ease, border-color .28s ease, background .28s ease;
}
.site-header[data-scrolled] {
  padding: 6px 0;
  background: rgba(255, 255, 255, .92);
  border-bottom-color: var(--line);
}

.header-rail {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: rgba(201, 214, 240, .55);
  overflow: hidden;
}
.header-rail__bar {
  display: block;
  height: 100%;
  width: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--pulse), var(--blue) 58%, var(--orange));
  transition: transform .12s linear;
}

.header-shell {
  position: relative;
  width: min(1320px, calc(100% - 2 * var(--gutter)));
  margin-inline: auto;
  display: flex;
  align-items: center;
  gap: clamp(8px, 1.4vw, 20px);
  padding: 9px 10px 9px 16px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 999px;
  box-shadow: 0 1px 0 rgba(11, 42, 111, .04), 0 22px 44px -36px rgba(11, 42, 111, .8);
  transition: padding .28s ease, box-shadow .28s ease;
}
.site-header[data-scrolled] .header-shell {
  padding-block: 5px;
  box-shadow: 0 26px 50px -34px rgba(11, 42, 111, .85);
}

/* 品牌角标 */
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  flex: 0 0 auto;
}
.brand__mark {
  position: relative;
  display: inline-block;
  padding: 9px 10px 8px;
  font-family: var(--font-narrow);
  font-size: 14px;
  font-weight: 800;
  line-height: 1;
  letter-spacing: .04em;
  color: var(--white);
  background: var(--navy);
  border-radius: 4px;
}
.brand__mark::after {
  content: "";
  position: absolute;
  top: -1px;
  right: -1px;
  width: 7px;
  height: 7px;
  background: var(--orange);
}
.brand__text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}
.brand__line {
  font-size: 14px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -.01em;
  color: var(--navy);
  white-space: nowrap;
}
.brand__sub {
  font-family: var(--font-narrow);
  font-size: 10px;
  line-height: 1.2;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--gray);
  white-space: nowrap;
}

/* 导航胶囊 */
.site-nav { margin-inline: auto; min-width: 0; }
.site-nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 4px;
  background: var(--ice);
  border: 1px solid var(--line);
  border-radius: 999px;
}
.site-nav__link {
  position: relative;
  display: block;
  padding: 8px 13px;
  font-size: 14px;
  font-weight: 600;
  line-height: 1.3;
  color: var(--navy);
  border-radius: 999px;
  white-space: nowrap;
  transition: background .2s ease, color .2s ease;
}
.site-nav__link:hover { background: rgba(27, 79, 216, .1); }
.site-nav__link[aria-current="page"] {
  color: var(--blue);
  background: var(--white);
}
.site-nav__link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 13px;
  right: 13px;
  bottom: 2px;
  height: 2px;
  background: var(--orange);
}

/* 工具区 */
.header-tools {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: auto;
  flex: 0 0 auto;
}
.lang-switch {
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 3px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 999px;
}
.lang-switch__btn {
  padding: 5px 9px;
  font-family: var(--font-narrow);
  font-size: 12px;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: .04em;
  color: var(--gray);
  border-radius: 999px;
  transition: background .2s ease, color .2s ease;
}
.lang-switch__btn:hover { color: var(--blue); }
.lang-switch__btn[aria-pressed="true"] {
  background: var(--navy);
  color: var(--white);
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 13px;
  font-weight: 700;
  line-height: 1.2;
  color: var(--navy);
}
.nav-toggle__bars { display: grid; gap: 3px; width: 16px; }
.nav-toggle__bars span {
  display: block;
  height: 2px;
  background: var(--navy);
  transition: transform .2s ease, opacity .2s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }
.nav-toggle[aria-expanded="true"] { border-color: var(--blue); color: var(--blue); }

/* 6. 按钮 ---------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 20px;
  font-size: 14px;
  font-weight: 700;
  line-height: 1;
  text-align: center;
  border: 1px solid transparent;
  border-radius: var(--radius);
  transition: transform .18s ease, background .18s ease, color .18s ease, border-color .18s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn--primary { background: var(--blue); border-color: var(--blue); color: var(--white); }
.btn--primary:hover { background: var(--navy); border-color: var(--navy); }
.btn--orange { background: var(--orange); border-color: var(--orange); color: var(--navy); }
.btn--orange:hover { background: #ff7f48; border-color: #ff7f48; }
.btn--ghost { background: transparent; border-color: var(--line); color: var(--navy); }
.btn--ghost:hover { border-color: var(--blue); color: var(--blue); }
.btn--sm { padding: 10px 15px; font-size: 13px; }

/* 7. 容器与栅格 ----------------------------------------------------------- */
.container { width: min(1320px, calc(100% - 2 * var(--gutter))); margin-inline: auto; }
.container--narrow { width: min(920px, calc(100% - 2 * var(--gutter))); margin-inline: auto; }
.container--wide { width: min(1560px, calc(100% - 2 * var(--gutter))); margin-inline: auto; }

.grid { display: grid; gap: var(--gap); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }
.split { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 0; }

/* 8. 章节标题（中英同基线并排） ------------------------------------------- */
.eyebrow {
  display: inline-block;
  margin-bottom: 10px;
  font-family: var(--font-narrow);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--blue);
}
.section-head {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: end;
  gap: 6px 18px;
  margin-bottom: 24px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}
.section-head__zh {
  font-size: clamp(24px, 3vw, 40px);
  font-weight: 800;
  letter-spacing: -.01em;
  line-height: 1.15;
  color: var(--navy);
}
.section-head__en {
  font-family: var(--font-narrow);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--gray);
  text-align: right;
}

/* 9. 双语对照板 ----------------------------------------------------------- */
.board {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.board__row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  border-top: 1px solid var(--line);
  transition: background .2s ease;
}
.board__row:first-child { border-top: 0; }
.board__row:hover { background: var(--ice); }
.board__zh,
.board__en { padding: 15px 18px; font-size: 15px; line-height: 1.75; }
.board__zh { color: var(--graphite); }
.board__en {
  border-left: 1px solid var(--line);
  color: var(--gray);
  font-size: 14px;
}

/* 10. 卡片与数据块 -------------------------------------------------------- */
.card {
  position: relative;
  padding: 20px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
.card--data {
  background: linear-gradient(158deg, #FFFFFF 22%, var(--ice) 100%);
  border-color: #B9CBF0;
  box-shadow: 0 30px 48px -44px rgba(11, 42, 111, .9);
}
.card--data::before {
  content: "";
  position: absolute;
  top: -1px;
  left: -1px;
  width: 28px;
  height: 3px;
  background: var(--orange);
}
.card--offset { transform: translate(-8px, -8px); }

/* 11. 状态标记 ------------------------------------------------------------ */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 10px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--navy);
}
.chip--orange {
  background: rgba(255, 106, 43, .1);
  border-color: rgba(255, 106, 43, .45);
  color: #AE3D0A;
}
.chip--green {
  background: rgba(18, 184, 134, .12);
  border-color: rgba(18, 184, 134, .45);
  color: #0A6E51;
}

/* 12. 横向轨道 / 时间线 --------------------------------------------------- */
.rail {
  position: relative;
  overflow-x: auto;
  padding-bottom: 12px;
  scrollbar-color: var(--line) transparent;
}
.rail__track {
  display: flex;
  min-width: max-content;
  border-top: 1px solid var(--line);
}
.rail__node {
  position: relative;
  min-width: 190px;
  padding: 18px 22px 16px;
  border-left: 1px solid var(--line);
  background: transparent;
  transition: background .2s ease;
}
.rail__node:first-child { border-left: 0; }
.rail__node:hover { background: var(--ice); }
.rail__node--now::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--orange);
}
.rail__date {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .02em;
  color: var(--gray);
}
.rail__node--now .rail__date { color: #AE3D0A; }
.rail__title {
  margin-top: 4px;
  font-size: 14px;
  font-weight: 700;
  line-height: 1.5;
  color: var(--navy);
}

/* 13. 图片容器基础规则（共享外壳不放图片，页面阶段填充） ------------------ */
.media-frame {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--ice);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
.media-frame__img,
.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  opacity: .55;
  background-image: linear-gradient(90deg, rgba(201, 214, 240, .8) 1px, transparent 1px);
  background-size: calc(100% / 6) 100%;
}
.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--square { aspect-ratio: 1 / 1; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame__tag {
  position: absolute;
  z-index: 1;
  left: 0;
  bottom: 0;
  padding: 6px 10px;
  background: var(--navy);
  color: var(--white);
  font-family: var(--font-narrow);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .12em;
  text-transform: uppercase;
}

/* 14. 面包屑与正文 -------------------------------------------------------- */
.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-narrow);
  font-size: 12px;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--gray);
}
.breadcrumbs__item { display: inline-flex; align-items: center; gap: 8px; }
.breadcrumbs__link { color: var(--navy); font-weight: 700; }
.breadcrumbs__link:hover { color: var(--blue); }
.breadcrumbs__sep { color: var(--line); }
.breadcrumbs__item[aria-current="page"] { color: var(--gray); }

.prose {
  max-width: 72ch;
  font-size: 16px;
  line-height: 1.75;
  color: var(--graphite);
}
.prose > * + * { margin-top: 1em; }
.prose h2 { margin-top: 1.6em; font-size: clamp(20px, 2.2vw, 28px); }
.prose h3 { margin-top: 1.4em; font-size: clamp(17px, 1.6vw, 20px); }
.prose a {
  color: var(--blue);
  text-decoration: underline;
  text-underline-offset: 3px;
}
.prose a:hover { color: var(--navy); }
.prose ul, .prose ol { padding-left: 1.25em; }
.prose ul { list-style: square; }
.prose ol { list-style: decimal; }
.prose li + li { margin-top: .4em; }
.prose strong { color: var(--navy); }

/* 15. 滚动显现 ------------------------------------------------------------ */
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity .32s ease, transform .32s ease;
  transition-delay: var(--reveal-delay, 0ms);
}
html.js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* 16. 页脚：斜切深蓝档案台 ------------------------------------------------ */
.site-footer {
  position: relative;
  overflow: hidden;
  margin-top: clamp(48px, 7vw, 96px);
  padding-top: var(--seam);
  background: var(--navy);
  color: var(--white);
  clip-path: polygon(0 var(--seam), 100% 0, 100% 100%, 0 100%);
}
.footer-seam {
  position: absolute;
  top: -1px;
  left: -2%;
  right: -2%;
  height: 4px;
  transform: skewY(-1.489deg);
  transform-origin: 100% 0;
  background: linear-gradient(90deg, var(--orange), rgba(255, 106, 43, .38) 62%, rgba(255, 106, 43, .06));
  pointer-events: none;
}
.footer-glow {
  position: absolute;
  inset: auto -12% -34% -12%;
  height: 420px;
  pointer-events: none;
  background:
    radial-gradient(circle at 26% 24%, rgba(76, 123, 255, .5), transparent 62%),
    radial-gradient(circle at 80% 6%, rgba(255, 106, 43, .26), transparent 56%);
}
.footer-inner {
  position: relative;
  z-index: 1;
  width: min(1320px, calc(100% - 2 * var(--gutter)));
  margin-inline: auto;
  padding: clamp(36px, 5vw, 64px) 0 26px;
}
.footer-top {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1.9fr) minmax(0, 1.1fr);
  gap: clamp(24px, 3.4vw, 52px);
  padding-bottom: clamp(28px, 3.6vw, 44px);
  border-bottom: 1px solid rgba(201, 214, 240, .22);
}

.footer-brand { min-width: 0; }
.footer-brand__mark {
  display: inline-block;
  position: relative;
  padding: 9px 10px 8px;
  font-family: var(--font-narrow);
  font-size: 14px;
  font-weight: 800;
  line-height: 1;
  letter-spacing: .04em;
  color: var(--navy);
  background: var(--white);
  border-radius: 4px;
}
.footer-brand__mark::after {
  content: "";
  position: absolute;
  top: -1px;
  right: -1px;
  width: 7px;
  height: 7px;
  background: var(--orange);
}
.footer-brand__line {
  margin-top: 14px;
  font-size: 16px;
  font-weight: 800;
  letter-spacing: -.01em;
  color: var(--white);
}
.footer-brand__sub {
  font-family: var(--font-narrow);
  font-size: 10px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: rgba(201, 214, 240, .72);
}
.footer-brand__note {
  margin-top: 14px;
  font-size: 12.5px;
  line-height: 1.9;
  color: rgba(238, 243, 255, .68);
}

.footer-nav {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(16px, 2vw, 28px);
}
.footer-col { min-width: 0; }
.footer-col__title,
.footer-contact__title {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
  padding-bottom: 10px;
  margin-bottom: 8px;
  border-bottom: 1px solid rgba(201, 214, 240, .28);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: .04em;
  color: var(--white);
}
.footer-col__en {
  font-family: var(--font-narrow);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: rgba(201, 214, 240, .62);
}
.footer-col__list { display: grid; }
.footer-link {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, auto);
  align-items: baseline;
  gap: 8px;
  padding: 7px 0;
  border-bottom: 1px solid rgba(201, 214, 240, .14);
  font-size: 13px;
  line-height: 1.75;
  color: rgba(255, 255, 255, .88);
  transition: color .2s ease, border-color .2s ease;
}
.footer-link:hover {
  color: var(--white);
  border-bottom-color: var(--orange);
}
.footer-link__zh { min-width: 0; }
.footer-link__en {
  font-family: var(--font-narrow);
  font-size: 10px;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: rgba(201, 214, 240, .62);
  text-align: right;
}
.footer-link:hover .footer-link__en { color: var(--orange); }

.footer-contact { min-width: 0; }
.footer-contact__row {
  display: grid;
  grid-template-columns: 64px minmax(0, 1fr);
  gap: 10px;
  padding: 8px 0;
  border-bottom: 1px solid rgba(201, 214, 240, .14);
  font-size: 13px;
  line-height: 1.75;
}
.footer-contact__label {
  font-family: var(--font-narrow);
  font-size: 10px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: rgba(201, 214, 240, .62);
  padding-top: 4px;
}
.footer-contact__value {
  color: var(--white);
  word-break: break-word;
}
.footer-contact__note {
  margin-top: 12px;
  font-size: 12px;
  line-height: 1.85;
  color: rgba(238, 243, 255, .62);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 20px;
  padding-top: 18px;
}
.footer-legal {
  font-size: 12.5px;
  line-height: 1.8;
  color: rgba(238, 243, 255, .74);
}
.footer-legal .num { color: var(--white); }
.footer-tag {
  font-family: var(--font-narrow);
  font-size: 10px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: rgba(201, 214, 240, .58);
}

/* 17. 响应式：平板 -------------------------------------------------------- */
@media (max-width: 1180px) {
  .site-nav__link { padding: 8px 10px; font-size: 13px; }
  .brand__sub { display: none; }
  .footer-top { grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr); }
  .footer-contact { grid-column: 1 / -1; }
}

@media (max-width: 1024px) {
  .header-cta { display: none; }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-nav { gap: 14px; }
}

/* 18. 响应式：手机 / 平板导航形态 ---------------------------------------- */
@media (max-width: 900px) {
  .site-header { padding: 10px 0 8px; }
  .header-shell {
    padding: 7px 8px 7px 12px;
    gap: 8px;
    border-radius: 22px;
  }
  .site-header[data-scrolled] .header-shell { border-radius: 20px; }

  .nav-toggle { display: inline-flex; margin-left: auto; }
  .header-tools { margin-left: 0; gap: 6px; }

  .site-nav {
    position: absolute;
    top: calc(100% + 10px);
    left: 0;
    right: 0;
    margin: 0;
    padding: 10px;
    background: var(--white);
    border: 1px solid var(--line);
    border-radius: 18px;
    box-shadow: 0 30px 56px -34px rgba(11, 42, 111, .85);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity .22s ease, transform .22s ease, visibility .22s ease;
  }
  .site-nav[data-open] {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }
  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 0;
    background: transparent;
    border: 0;
    border-radius: 0;
  }
  .site-nav__link {
    padding: 12px 14px;
    font-size: 15px;
    border-radius: 10px;
    background: var(--ice);
  }
  .site-nav__link[aria-current="page"] {
    background: var(--white);
    box-shadow: inset 0 0 0 1px var(--line);
  }
  .site-nav__link[aria-current="page"]::after {
    left: 14px;
    right: auto;
    width: 18px;
    bottom: 8px;
  }
}

@media (max-width: 780px) {
  .grid--2,
  .grid--3 { grid-template-columns: minmax(0, 1fr); }
  .grid--12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .card--offset { transform: none; }

  .board__zh,
  .board__en { padding: 13px 12px; font-size: 13.5px; }
  .board__en { font-size: 12.5px; }

  .section-head {
    grid-template-columns: minmax(0, 1fr);
    align-items: start;
  }
  .section-head__en { text-align: left; }

  .footer-top { grid-template-columns: minmax(0, 1fr); }
  .footer-nav { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 560px) {
  .brand__line { font-size: 13px; }
  .brand__mark { padding: 8px 8px 7px; font-size: 12px; }
  .nav-toggle__label { display: none; }
  .lang-switch__btn { padding: 5px 7px; }
  .footer-nav { grid-template-columns: minmax(0, 1fr); }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
  .footer-contact__row { grid-template-columns: 56px minmax(0, 1fr); }
  .prose { max-width: none; }
}

/* 19. 减弱动效 ------------------------------------------------------------ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }
  html.js [data-reveal] {
    opacity: 1;
    transform: none;
  }
  .btn:hover { transform: none; }
  .header-rail__bar { transition: none; }
}