/* ============================================================
   雅博官网 · 共享样式表  /assets/site.css
   夜赛深蓝基底 · 草皮绿区块 · 荧光青数据线
   ============================================================ */

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

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

body, h1, h2, h3, h4, h5, p, ul, ol, figure, figcaption, blockquote, dl, dd { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video, canvas { display: block; max-width: 100%; }
button, input, select, textarea { font: inherit; color: inherit; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }

/* ---------- 2. 变量 ---------- */
:root {
  /* 色板 */
  --ink: #0B1B2B;
  --ink-deep: #06111C;
  --ink-2: #12283A;
  --grass: #1F5C3E;
  --grass-lite: #2F8A5C;
  --pulse: #31E2C8;
  --ref: #F3C13A;
  --risk: #D9403C;
  --orange: #F0854A;
  --orange-2: #F7B267;
  --paper: #F3F5F2;
  --gray: #8A97A3;
  --black: #101418;

  /* 语义文本与边界 */
  --text: #D6DFE5;
  --text-dim: #8A97A3;
  --line: rgba(243, 245, 242, 0.10);
  --line-strong: rgba(243, 245, 242, 0.22);

  /* 字体 */
  --font-display: "PingFang SC", "Noto Sans SC", "Microsoft YaHei", "Arial Narrow", "Helvetica Neue", sans-serif;
  --font-body: "PingFang SC", "Noto Sans SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
  --font-mono: "SFMono-Regular", "JetBrains Mono", Menlo, Consolas, "Courier New", monospace;

  /* 尺度 */
  --wrap: 1380px;
  --gutter: clamp(18px, 4vw, 48px);
  --header-h: 76px;
  --gap: clamp(16px, 2vw, 30px);
  --ease: cubic-bezier(0.2, 0.6, 0.25, 1);
}

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100vh;
  background-color: var(--ink);
  background-image:
    linear-gradient(rgba(243, 245, 242, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(243, 245, 242, 0.025) 1px, transparent 1px);
  background-size: 92px 92px;
  background-position: -1px -1px;
  color: var(--text);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.8;
  overflow-x: clip;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

h1, h2, h3, h4, h5 {
  font-family: var(--font-display);
  font-weight: 800;
  color: var(--paper);
  line-height: 1.14;
  letter-spacing: 0.01em;
}

h1 { font-size: clamp(2.2rem, 6vw, 4.4rem); line-height: 1.03; }
h2 { font-size: clamp(1.55rem, 3.4vw, 2.5rem); line-height: 1.12; }
h3 { font-size: clamp(1.12rem, 2vw, 1.45rem); }
h4 { font-size: 1.05rem; }

strong, b { color: var(--paper); font-weight: 700; }
small { font-size: 0.82em; }

::selection { background: var(--pulse); color: #04212a; }

:focus-visible {
  outline: 2px solid var(--pulse);
  outline-offset: 3px;
  border-radius: 1px;
}

/* ---------- 4. 工具类 ---------- */
.container {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.container--narrow { max-width: 980px; }

.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;
}

.stack { display: flex; flex-direction: column; gap: clamp(14px, 1.6vw, 22px); }

.data,
.field {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.06em;
}

.field { font-size: 12px; line-height: 1.7; color: var(--text-dim); }
.data { font-size: 13px; color: var(--pulse); }

/* ---------- 5. 网格与区块 ---------- */
.grid {
  display: grid;
  gap: var(--gap);
  grid-template-columns: repeat(12, minmax(0, 1fr));
}

.grid--split { grid-template-columns: repeat(12, minmax(0, 1fr)); }
.grid--split > .col-index { grid-column: 1 / span 4; }
.grid--split > .col-main { grid-column: 5 / span 8; }

.grid--split-rev > .col-main { grid-column: 1 / span 8; }
.grid--split-rev > .col-index { grid-column: 9 / span 4; }

.grid--cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }

.section { padding-block: clamp(48px, 8vw, 112px); }

.section-band {
  background: rgba(18, 40, 58, 0.55);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding-block: clamp(38px, 6vw, 78px);
}

.section--paper {
  background: var(--paper);
  color: var(--ink);
  border-top: 1px solid rgba(16, 20, 24, 0.12);
  border-bottom: 1px solid rgba(16, 20, 24, 0.12);
}

.section--paper h1,
.section--paper h2,
.section--paper h3,
.section--paper h4 { color: var(--black); }

.section--paper .lede,
.section--paper p { color: #2A3B47; }

.panel {
  background: var(--ink-2);
  border: 1px solid var(--line);
  box-shadow: 0 1px 0 rgba(243, 245, 242, 0.03), 0 22px 44px -34px rgba(0, 0, 0, 0.95);
  padding: clamp(18px, 2.4vw, 32px);
}

.panel--paper {
  background: var(--paper);
  border-color: rgba(16, 20, 24, 0.14);
  color: var(--ink);
}

.panel--paper h1,
.panel--paper h2,
.panel--paper h3 { color: var(--black); }

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 13px 24px;
  border: 1px solid transparent;
  font-family: var(--font-body);
  font-size: 13px;
  letter-spacing: 0.14em;
  line-height: 1;
  cursor: pointer;
  transition: background-color 0.18s var(--ease), border-color 0.18s var(--ease), color 0.18s var(--ease), transform 0.18s var(--ease);
}

.btn--primary {
  background: var(--grass);
  border-color: var(--grass);
  color: var(--paper);
}

.btn--primary:hover {
  background: var(--grass-lite);
  border-color: var(--grass-lite);
  transform: translateY(-1px);
}

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

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

.btn--pulse {
  background: var(--pulse);
  border-color: var(--pulse);
  color: #04212a;
  font-weight: 700;
}

.btn--pulse:hover { background: #57efd8; border-color: #57efd8; }

/* ---------- 7. 排版组件 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--grass-lite);
}

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

.display {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2.6rem, 9vw, 8.4rem);
  line-height: 0.92;
  letter-spacing: -0.01em;
  text-transform: uppercase;
  color: var(--paper);
}

.display--outline {
  color: transparent;
  -webkit-text-stroke: 1px rgba(243, 245, 242, 0.32);
}

.lede {
  font-size: clamp(1rem, 1.4vw, 1.12rem);
  line-height: 1.85;
  color: var(--text-dim);
  max-width: 62ch;
}

.stat-value {
  display: block;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(2.4rem, 7vw, 5.4rem);
  line-height: 0.88;
  letter-spacing: -0.02em;
  color: var(--paper);
  font-variant-numeric: tabular-nums;
}

.stat-label {
  display: block;
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--text-dim);
}

.prose { font-size: 17px; line-height: 1.85; color: var(--text); }
.prose > * + * { margin-top: 1.2em; }
.prose h2 { margin-top: 2em; }
.prose h3 { margin-top: 1.6em; }
.prose a {
  color: var(--pulse);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}
.prose a:hover { background: rgba(49, 226, 200, 0.12); }
.prose ul, .prose ol { list-style: disc; padding-left: 1.4em; }
.prose ol { list-style: decimal; }
.prose li + li { margin-top: 0.5em; }

/* ---------- 8. 语义标签 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 4px 10px;
  border: 1px solid currentColor;
  background: rgba(243, 245, 242, 0.03);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  line-height: 1.6;
  color: var(--gray);
  white-space: nowrap;
}

.tag--grass { color: var(--grass-lite); background: rgba(47, 138, 92, 0.12); }
.tag--pulse { color: var(--pulse); background: rgba(49, 226, 200, 0.09); }
.tag--ref { color: var(--ref); background: rgba(243, 193, 58, 0.09); }
.tag--risk { color: var(--risk); background: rgba(217, 64, 60, 0.12); }
.tag--transfer { color: var(--orange); background: rgba(240, 133, 74, 0.11); }

/* ---------- 9. 面包屑 ---------- */
.breadcrumb {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--gray);
}

.breadcrumb-list { display: flex; flex-wrap: wrap; align-items: center; gap: 0; }

.breadcrumb-item { display: inline-flex; align-items: center; }

.breadcrumb-item + .breadcrumb-item::before {
  content: "/";
  margin: 0 10px;
  color: rgba(243, 245, 242, 0.24);
}

.breadcrumb-item a { color: var(--gray); transition: color 0.18s var(--ease); }
.breadcrumb-item a:hover { color: var(--pulse); }

.breadcrumb-current { color: var(--paper); }

/* ---------- 10. 图片容器 ---------- */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line);
  background-color: var(--ink-2);
  background-image:
    linear-gradient(150deg, rgba(31, 92, 62, 0.42), rgba(11, 27, 43, 0.92) 62%),
    repeating-linear-gradient(45deg, rgba(243, 245, 242, 0.03) 0 1px, transparent 1px 13px);
  box-shadow: 0 26px 52px -40px rgba(0, 0, 0, 0.95);
}

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

.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--std { aspect-ratio: 16 / 9; }
.media-frame--tall { aspect-ratio: 4 / 5; }
.media-frame--square { aspect-ratio: 1 / 1; }

.media-frame--scrim::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(11, 27, 43, 0) 42%, rgba(6, 17, 28, 0.82));
  pointer-events: none;
}

/* ---------- 11. 目录 ---------- */
.toc {
  border-left: 1px solid var(--line);
  padding-left: clamp(14px, 1.6vw, 22px);
}

.toc-title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gray);
  margin-bottom: 14px;
}

.toc-list { display: flex; flex-direction: column; }

.toc-link {
  display: block;
  margin-left: -1px;
  padding: 9px 0 9px 14px;
  border-left: 1px solid transparent;
  font-size: 13px;
  letter-spacing: 0.06em;
  line-height: 1.5;
  color: var(--text-dim);
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

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

.toc-link[aria-current="true"] {
  color: var(--pulse);
  border-left-color: var(--pulse);
}

/* ---------- 12. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 200;
  padding: 11px 20px;
  background: var(--pulse);
  color: #04212a;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.1em;
  transform: translateY(-180%);
  transition: transform 0.16s var(--ease);
}

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

/* ---------- 13. 页头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(11, 27, 43, 0.92);
  -webkit-backdrop-filter: saturate(140%) blur(12px);
  backdrop-filter: saturate(140%) blur(12px);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  min-height: var(--header-h);
  padding: 12px var(--gutter);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: clamp(14px, 2.4vw, 36px);
}

/* 品牌区 */
.brand-block {
  display: flex;
  align-items: center;
  gap: clamp(14px, 2vw, 26px);
  min-width: 0;
}

.brand-mark {
  display: inline-flex;
  align-items: baseline;
  gap: 9px;
  padding: 6px 0;
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1;
  white-space: nowrap;
}

.brand-mark-cn {
  font-size: clamp(19px, 1.7vw, 23px);
  letter-spacing: 0.14em;
  color: var(--paper);
}

.brand-mark-latin {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 400;
  letter-spacing: 0.3em;
  color: var(--grass-lite);
  padding-bottom: 2px;
}

.brand-mark:hover .brand-mark-cn { color: var(--pulse); }

.brand-meta {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding-left: clamp(14px, 2vw, 24px);
  border-left: 1px solid var(--line);
  min-width: 0;
}

.brand-tagline {
  font-size: 12px;
  letter-spacing: 0.06em;
  line-height: 1.4;
  color: var(--text-dim);
  white-space: nowrap;
}

.version-strip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: rgba(138, 151, 163, 0.82);
  white-space: nowrap;
}

.version-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--pulse);
  animation: version-pulse 2.6s ease-in-out infinite;
}

@keyframes version-pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(49, 226, 200, 0.55); }
  50% { box-shadow: 0 0 0 6px rgba(49, 226, 200, 0); }
}

/* 导航 */
.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(12px, 1.8vw, 28px);
}

.nav-list {
  display: flex;
  align-items: center;
  gap: clamp(4px, 1vw, 16px);
}

.nav-link {
  position: relative;
  display: inline-block;
  padding: 9px 7px;
  font-size: 14px;
  letter-spacing: 0.08em;
  line-height: 1.4;
  color: var(--text-dim);
  white-space: nowrap;
  transition: color 0.18s var(--ease);
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 7px;
  right: 7px;
  bottom: 2px;
  height: 1px;
  background: var(--pulse);
  transform: scaleX(0);
  transform-origin: right center;
  transition: transform 0.2s var(--ease), background-color 0.2s var(--ease);
}

.nav-link:hover { color: var(--paper); }
.nav-link:hover::after { transform: scaleX(1); transform-origin: left center; }

.nav-link[aria-current="page"] { color: var(--paper); }
.nav-link[aria-current="page"]::after { transform: scaleX(1); }

.header-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 11px 20px;
  border: 1px solid var(--grass-lite);
  background: linear-gradient(180deg, rgba(47, 138, 92, 0.24), rgba(31, 92, 62, 0.1));
  color: var(--paper);
  font-size: 13px;
  letter-spacing: 0.14em;
  line-height: 1;
  white-space: nowrap;
  transition: background-color 0.18s var(--ease), border-color 0.18s var(--ease), color 0.18s var(--ease);
}

.header-action:hover {
  background: var(--grass-lite);
  border-color: var(--grass-lite);
  color: #06131d;
}

/* 移动端按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 11px;
  padding: 10px 14px;
  border: 1px solid var(--line-strong);
  background: transparent;
  color: var(--paper);
  font-size: 12px;
  letter-spacing: 0.16em;
  line-height: 1;
  cursor: pointer;
  transition: border-color 0.18s var(--ease), color 0.18s var(--ease);
}

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

.nav-toggle-bars {
  position: relative;
  display: inline-block;
  width: 18px;
  height: 11px;
}

.nav-toggle-bars::before,
.nav-toggle-bars::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 1.5px;
  background: currentColor;
  transition: transform 0.18s var(--ease);
}

.nav-toggle-bars::before { top: 0; }
.nav-toggle-bars::after { bottom: 0; }

.nav-toggle[aria-expanded="true"] .nav-toggle-bars::before { transform: translateY(4.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle-bars::after { transform: translateY(-4.5px) rotate(-45deg); }

/* 滚动进度 */
.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  overflow: hidden;
}

.scroll-progress-bar {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: left center;
  background: linear-gradient(90deg, var(--grass-lite), var(--pulse));
  will-change: transform;
}

/* ---------- 14. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 9vw, 130px);
  background: var(--ink-deep);
  border-top: 1px solid var(--line);
  color: var(--text-dim);
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 2px;
  background: linear-gradient(90deg, var(--grass) 0%, var(--pulse) 34%, var(--ref) 66%, var(--orange) 100%);
  opacity: 0.8;
}

.footer-inner {
  max-width: var(--wrap);
  margin-inline: auto;
  padding: clamp(52px, 7vw, 92px) var(--gutter) clamp(34px, 4vw, 56px);
  display: grid;
  grid-template-columns: minmax(220px, 1.25fr) repeat(4, minmax(0, 1fr));
  gap: clamp(26px, 3.2vw, 52px);
  align-items: start;
}

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

.footer-brand {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.35rem, 2.4vw, 1.9rem);
  letter-spacing: 0.12em;
  line-height: 1.2;
  color: var(--paper);
}

.footer-brand-sub {
  margin-top: 10px;
  font-size: 13px;
  letter-spacing: 0.06em;
  line-height: 1.7;
  color: var(--text-dim);
  max-width: 26ch;
}

.footer-col-title {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--paper);
}

.footer-col-title::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--line);
}

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

.footer-list a {
  display: inline-block;
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-dim);
  border-bottom: 1px solid transparent;
  transition: color 0.18s var(--ease), border-color 0.18s var(--ease);
}

.footer-list a:hover {
  color: var(--pulse);
  border-bottom-color: rgba(49, 226, 200, 0.5);
}

.footer-list--contact .field { display: block; color: var(--text-dim); }

.footer-base {
  border-top: 1px solid var(--line);
  background: rgba(0, 0, 0, 0.22);
}

.footer-base-inner {
  max-width: var(--wrap);
  margin-inline: auto;
  padding: 20px var(--gutter) 32px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 30px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--gray);
}

.footer-note { max-width: 52ch; line-height: 1.7; }

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 20px;
}

.footer-icp { color: var(--gray); }
.footer-copy { color: rgba(138, 151, 163, 0.75); }

/* ---------- 15. 显现动效 ---------- */
html.js-reveal [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.55s var(--ease), transform 0.55s var(--ease);
}

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

@media (prefers-reduced-motion: no-preference) {
  .media-frame > img { transition: transform 0.5s var(--ease); }
  .media-frame:hover > img { transform: scale(1.02); }
}

/* ---------- 16. 响应式 ---------- */
@media (max-width: 1180px) {
  .brand-meta { display: none; }
  .grid--cols-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 1000px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: fixed;
    inset: 0 0 0 auto;
    z-index: 70;
    width: min(88vw, 400px);
    padding: calc(var(--header-h) + 30px) clamp(20px, 6vw, 36px) 44px;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 26px;
    background: var(--ink-2);
    border-left: 1px solid var(--line);
    box-shadow: -30px 0 60px -40px rgba(0, 0, 0, 0.95);
    overflow-y: auto;
    transform: translateX(101%);
    visibility: hidden;
    transition: transform 0.22s var(--ease), visibility 0.22s linear;
  }

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

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    width: 100%;
  }

  .nav-item { border-bottom: 1px solid var(--line); }

  .nav-link {
    display: block;
    width: 100%;
    padding: 16px 2px;
    font-size: 16px;
  }

  .nav-link::after { left: 2px; right: auto; width: 20px; bottom: 9px; }
  .nav-link:hover::after { transform: scaleX(1); }
  .nav-link[aria-current="page"]::after { transform: scaleX(1); }

  .header-action {
    width: 100%;
    padding: 16px 22px;
    font-size: 14px;
  }

  .grid--split > .col-index,
  .grid--split > .col-main,
  .grid--split-rev > .col-index,
  .grid--split-rev > .col-main { grid-column: 1 / -1; }

  .toc { border-left: 0; padding-left: 0; }
  .toc-list { flex-direction: row; flex-wrap: wrap; gap: 4px 16px; }
  .toc-link { border-left: 0; border-bottom: 1px solid transparent; padding: 6px 0; }

  .footer-inner { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-lead { grid-column: 1 / -1; }
}

@media (max-width: 900px) {
  .grid--cols-3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  :root { --header-h: 68px; }

  body { font-size: 16px; }

  .header-inner { padding: 10px var(--gutter); }
  .brand-mark-cn { letter-spacing: 0.1em; }
  .brand-mark-latin { display: none; }

  .grid--cols-2,
  .grid--cols-3,
  .grid--cols-4 { grid-template-columns: minmax(0, 1fr); }

  .footer-inner { grid-template-columns: minmax(0, 1fr); }
  .footer-lead { grid-column: auto; }

  .footer-base-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .media-frame--tall { aspect-ratio: 4 / 5; }
}

/* ---------- 17. 减弱动效 ---------- */
@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.js-reveal [data-reveal] { opacity: 1; transform: none; }

  .media-frame:hover > img { transform: none; }
  .btn--primary:hover { transform: none; }
}