/* ============================================================
   爱博国看台 · /assets/site.css
   共享外壳样式：reset / 变量 / 中文排版 / 头部 / 页脚 / 基础组件
   ============================================================ */

/* ---------- 1. 变量 ---------- */
:root {
  --navy-900: #0A1424;
  --navy-800: #101D33;
  --navy-700: #16263F;
  --aqua: #2FE0D0;
  --aqua-deep: #1A8F89;
  --amber: #F5B84A;
  --rose: #E5496F;
  --paper: #E6EDF5;
  --mist: #8FA3B8;
  --line: #21344D;
  --ink: #04121A;

  --shell: 1180px;
  --gut: clamp(16px, 4vw, 40px);

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

  --ease: cubic-bezier(.32, .72, .28, 1);
}

/* ---------- 2. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

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

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

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

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

a {
  color: var(--aqua);
  text-decoration: none;
  transition: color .18s var(--ease), border-color .18s var(--ease);
}

a:hover { color: #7FF0E6; }

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

[id] { scroll-margin-top: 132px; }

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100vh;
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 400;
  line-height: 1.75;
  color: var(--paper);
  background-color: var(--navy-900);
  background-image:
    radial-gradient(1100px 560px at 88% -8%, rgba(47, 224, 208, .10), transparent 62%),
    radial-gradient(900px 520px at -6% 100%, rgba(245, 184, 74, .06), transparent 60%);
  background-attachment: fixed;
  -webkit-font-smoothing: antialiased;
}

/* 全站扫描线底噪 */
body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  opacity: .55;
  background-image: repeating-linear-gradient(
    180deg,
    rgba(230, 237, 245, .028) 0 1px,
    transparent 1px 4px
  );
}

h1, h2, h3, h4, h5 {
  font-family: var(--font-display);
  font-weight: 600;
  line-height: 1.28;
  letter-spacing: .04em;
  color: var(--paper);
}

h1 { font-size: clamp(28px, 4.4vw, 48px); }
h2 { font-size: clamp(22px, 2.8vw, 32px); }
h3 { font-size: clamp(17px, 1.9vw, 21px); }

p { margin: 0 0 1.05em; }
p:last-child { margin-bottom: 0; }

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: .04em;
}

/* ---------- 4. 通用容器与分区 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: var(--gut);
}

.section { padding-block: clamp(48px, 7vw, 88px); position: relative; }
.section--tight { padding-block: clamp(26px, 4vw, 48px); }

.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 22px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
  margin-bottom: clamp(20px, 3vw, 36px);
}

.section__eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--aqua);
}

.section__title { font-size: clamp(20px, 2.6vw, 30px); }

.section__note {
  margin-left: auto;
  max-width: 48ch;
  font-size: 13px;
  line-height: 1.8;
  color: var(--mist);
}

/* ---------- 5. 网格 ---------- */
.grid { display: grid; gap: clamp(14px, 2vw, 24px); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid--split { grid-template-columns: minmax(0, 1.65fr) minmax(0, 1fr); }

@media (max-width: 1040px) {
  .grid--3, .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid--split { grid-template-columns: minmax(0, 1fr); }
}

@media (max-width: 660px) {
  .grid--2, .grid--3, .grid--4 { grid-template-columns: minmax(0, 1fr); }
}

.prose { max-width: 74ch; }
.prose p { margin-bottom: 1.1em; }
.prose h2 { margin: 2em 0 .7em; }
.prose h3 { margin: 1.6em 0 .6em; }
.prose ul, .prose ol { padding-left: 1.4em; margin-bottom: 1.1em; }
.prose ul { list-style: square; }
.prose ol { list-style: decimal; }
.prose li { margin-block: .35em; }
.prose strong { color: #FFFFFF; font-weight: 600; }
.prose code {
  font-family: var(--font-mono);
  font-size: .9em;
  padding: .08em .42em;
  border: 1px solid var(--line);
  background: var(--navy-700);
  color: var(--amber);
}

/* ---------- 6. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 12px 22px;
  border: 1px solid var(--line);
  background: var(--navy-800);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  transition: background .2s var(--ease), border-color .2s var(--ease), color .2s var(--ease), transform .2s var(--ease);
}

.btn:hover {
  color: var(--aqua);
  border-color: var(--aqua);
  background: rgba(47, 224, 208, .08);
}

.btn--primary {
  background: var(--aqua);
  border-color: var(--aqua);
  color: var(--ink);
  font-weight: 600;
}

.btn--primary:hover {
  background: #6BF0E4;
  border-color: #6BF0E4;
  color: var(--ink);
}

.btn--ghost { background: transparent; }
.btn--ghost:hover { background: rgba(47, 224, 208, .06); }

/* ---------- 7. 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .1em;
  color: var(--mist);
}

.breadcrumb__item { display: flex; align-items: center; gap: 8px; }
.breadcrumb__item + .breadcrumb__item::before { content: "/"; color: var(--line); }
.breadcrumb__link { color: var(--mist); }
.breadcrumb__link:hover { color: var(--aqua); }
.breadcrumb__current { color: var(--paper); }

/* ---------- 8. 卡片 / 列表 / 数据块 ---------- */
.card {
  position: relative;
  padding: clamp(16px, 2.4vw, 26px);
  border: 1px solid var(--line);
  background: linear-gradient(180deg, var(--navy-800), rgba(16, 29, 51, .5));
  box-shadow: 0 1px 0 rgba(230, 237, 245, .03);
  transition: border-color .22s var(--ease), background .22s var(--ease);
}

.card::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 2px;
  background: linear-gradient(180deg, var(--aqua), transparent 78%);
  opacity: .55;
}

.card:hover { border-color: #2B425E; }
.card--amber::before { background: linear-gradient(180deg, var(--amber), transparent 78%); }
.card--rose::before { background: linear-gradient(180deg, var(--rose), transparent 78%); }

.card__title { font-size: 17px; margin-bottom: 8px; }

.card__meta {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--mist);
}

.stat { display: flex; flex-direction: column; gap: 8px; }

.stat__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: clamp(32px, 5vw, 58px);
  line-height: 1;
  letter-spacing: -.01em;
  color: var(--amber);
}

.stat__unit {
  font-size: .38em;
  margin-left: 8px;
  letter-spacing: .12em;
  color: var(--mist);
}

.stat__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--mist);
}

.stat--aqua .stat__value { color: var(--aqua); }
.stat--rose .stat__value { color: var(--rose); }

.index-list { border-top: 1px solid var(--line); }

.index-list__item {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: baseline;
  gap: 6px 18px;
  padding: 14px 6px;
  border-bottom: 1px solid var(--line);
  transition: background .2s var(--ease);
}

.index-list__item:hover { background: rgba(47, 224, 208, .05); }

.index-list__no {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--aqua);
}

.index-list__title { font-size: 15.5px; color: var(--paper); }

.index-list__meta {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  color: var(--mist);
  white-space: nowrap;
}

.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--line);
  background: var(--navy-800);
  -webkit-overflow-scrolling: touch;
}

.data-table {
  width: 100%;
  min-width: 640px;
  border-collapse: collapse;
  font-size: 14px;
}

.data-table th,
.data-table td {
  padding: 11px 14px;
  text-align: left;
  border-bottom: 1px solid var(--line);
}

.data-table thead th {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--amber);
  background: rgba(22, 38, 63, .9);
  white-space: nowrap;
}

.data-table tbody tr:nth-child(even) { background: rgba(22, 38, 63, .42); }
.data-table tbody tr:hover { background: rgba(47, 224, 208, .07); }
.data-table .num,
.data-table td.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: .04em;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  border: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--mist);
  white-space: nowrap;
}

.tag--aqua { color: var(--aqua); border-color: rgba(47, 224, 208, .42); }
.tag--amber { color: var(--amber); border-color: rgba(245, 184, 74, .42); }
.tag--rose { color: var(--rose); border-color: rgba(229, 73, 111, .48); }

.marginalia {
  padding: 2px 0 2px 14px;
  border-left: 2px solid var(--aqua-deep);
  font-size: 13.5px;
  line-height: 1.8;
  color: var(--mist);
}

.marginalia__label {
  display: block;
  margin-bottom: 4px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--aqua);
}

/* 章节目录 */
.toc {
  padding: 14px 16px;
  border: 1px solid var(--line);
  background: rgba(16, 29, 51, .62);
}

.toc__title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--amber);
  margin-bottom: 10px;
}

.toc__link {
  display: block;
  padding: 6px 0 6px 10px;
  border-left: 2px solid transparent;
  font-size: 13.5px;
  color: var(--mist);
}

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

.toc__link[aria-current="true"] {
  color: var(--aqua);
  border-left-color: var(--aqua);
  background: rgba(47, 224, 208, .07);
}

/* ---------- 9. 图像容器基础规则 ---------- */
.media { display: block; margin: 0; }

.media__frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  border: 1px solid var(--line);
  background: var(--navy-800);
}

.media__frame img,
.media__frame picture > img,
.media__frame video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.86) contrast(1.06);
}

.media__frame::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(180deg, rgba(10, 20, 36, .12), rgba(10, 20, 36, .58)),
    repeating-linear-gradient(180deg, rgba(47, 224, 208, .05) 0 1px, transparent 1px 5px);
}

.media--3-2 .media__frame { aspect-ratio: 3 / 2; }
.media--1-1 .media__frame { aspect-ratio: 1 / 1; }
.media--tall .media__frame { aspect-ratio: 4 / 5; }
.media--wide .media__frame { aspect-ratio: 21 / 9; }

.media__caption {
  margin-top: 10px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .06em;
  line-height: 1.7;
  color: var(--mist);
}

.media__tag {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 2;
  padding: 5px 10px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: rgba(10, 20, 36, .82);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--amber);
}

/* ---------- 10. 跳转链接 ---------- */
.skip-link {
  position: absolute;
  left: 14px;
  top: -72px;
  z-index: 140;
  padding: 10px 18px;
  background: var(--aqua);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .1em;
  transition: top .2s var(--ease);
}

.skip-link:focus { top: 12px; color: var(--ink); }

/* ---------- 11. 头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  border-bottom: 1px solid var(--line);
  background: rgba(10, 20, 36, .93);
  -webkit-backdrop-filter: blur(10px) saturate(1.2);
  backdrop-filter: blur(10px) saturate(1.2);
}

.header-scan {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1px;
  overflow: hidden;
  pointer-events: none;
}

.header-scan::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent, rgba(47, 224, 208, .85), transparent);
  transform: translateX(-100%);
  animation: header-scan-move 7s linear infinite;
}

@keyframes header-scan-move {
  to { transform: translateX(100%); }
}

.header-upper { position: relative; }

.header-upper__inner {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto auto;
  align-items: center;
  gap: 8px 28px;
  padding-block: 14px 12px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--paper);
}

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

.brand__mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  flex: none;
  border: 1px solid var(--line);
  background: var(--navy-800);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--aqua);
}

.brand__text { display: flex; flex-direction: column; gap: 3px; }

.brand__name {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 600;
  letter-spacing: .18em;
  text-transform: uppercase;
  line-height: 1.1;
}

.brand__tagline {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--mist);
}

.brand__subline {
  justify-self: start;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--mist);
  white-space: nowrap;
}

.utility-nav {
  display: flex;
  align-items: center;
  gap: 20px;
  justify-self: end;
}

.utility-nav__link {
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
  font-size: 12.5px;
  letter-spacing: .08em;
  color: var(--mist);
}

.utility-nav__link:hover {
  color: var(--aqua);
  border-bottom-color: var(--aqua);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  padding: 9px 14px;
  border: 1px solid var(--line);
  background: var(--navy-800);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  justify-self: end;
}

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

.nav-toggle__bar {
  position: relative;
  display: block;
  width: 14px;
  height: 1px;
  background: var(--aqua);
  transition: background .2s var(--ease);
}

.nav-toggle__bar::before,
.nav-toggle__bar::after {
  content: "";
  position: absolute;
  left: 0;
  width: 14px;
  height: 1px;
  background: var(--aqua);
  transition: transform .2s var(--ease), top .2s var(--ease);
}

.nav-toggle__bar::before { top: -5px; }
.nav-toggle__bar::after { top: 5px; }

.nav-toggle[data-active="on"] .nav-toggle__bar { background: transparent; }
.nav-toggle[data-active="on"] .nav-toggle__bar::before { top: 0; transform: rotate(45deg); }
.nav-toggle[data-active="on"] .nav-toggle__bar::after { top: 0; transform: rotate(-45deg); }

.nav-toggle__label { line-height: 1; }

.header-lower {
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(16, 29, 51, .9), rgba(10, 20, 36, .92));
}

.site-nav__list {
  display: flex;
  align-items: stretch;
  gap: 2px;
  overflow-x: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--line) transparent;
}

.site-nav__list::-webkit-scrollbar { height: 4px; }
.site-nav__list::-webkit-scrollbar-thumb { background: var(--line); }

.site-nav__item { flex: none; }

.site-nav__link {
  display: flex;
  align-items: baseline;
  gap: 9px;
  padding: 12px 18px;
  border-bottom: 2px solid transparent;
  color: var(--paper);
  font-size: 14px;
  letter-spacing: .04em;
  white-space: nowrap;
}

.site-nav__link:hover {
  color: var(--aqua);
  background: rgba(47, 224, 208, .07);
}

.site-nav__index {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--mist);
}

.site-nav__label { line-height: 1.2; }

.site-nav__link[aria-current="page"] {
  color: var(--aqua);
  border-bottom-color: var(--aqua);
  background: rgba(47, 224, 208, .09);
}

.site-nav__link[aria-current="page"] .site-nav__index { color: var(--amber); }

/* ---------- 12. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 8vw, 96px);
  border-top: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(16, 29, 51, .88), var(--navy-900));
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: min(260px, 42%);
  height: 1px;
  background: linear-gradient(90deg, var(--aqua), transparent);
}

.footer__inner {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr) minmax(0, 1.15fr);
  gap: clamp(24px, 4vw, 56px);
  padding-block: clamp(36px, 6vw, 66px);
}

.footer__col { min-width: 0; }

.footer__brand {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 600;
  letter-spacing: .18em;
  color: var(--paper);
}

.footer__statement {
  margin-top: 12px;
  max-width: 42ch;
  font-size: 13.5px;
  line-height: 1.85;
  color: var(--mist);
}

.footer__meta {
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--aqua-deep);
}

.footer__heading {
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--amber);
}

.footer__list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 9px 18px;
}

.footer__link {
  font-size: 13.5px;
  color: var(--mist);
  border-bottom: 1px solid transparent;
}

.footer__link:hover {
  color: var(--aqua);
  border-bottom-color: rgba(47, 224, 208, .5);
}

.footer__contact { display: grid; gap: 10px; }

.footer__contact-row {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 10px;
  align-items: baseline;
}

.footer__label {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--aqua-deep);
}

.footer__value {
  font-size: 13.5px;
  color: var(--paper);
  word-break: break-word;
}

.footer__note {
  margin-top: 16px;
  padding-left: 12px;
  border-left: 2px solid var(--line);
  font-size: 12.5px;
  line-height: 1.8;
  color: var(--mist);
}

.footer__base {
  border-top: 1px solid var(--line);
  background: rgba(10, 20, 36, .6);
}

.footer__base-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  padding-block: 16px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .1em;
  color: var(--mist);
}

.footer__icp { color: var(--mist); }

/* ---------- 13. 进度条 / 返回顶部 ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 120;
  height: 2px;
  pointer-events: none;
  background: rgba(33, 52, 77, .6);
}

.scroll-progress__bar {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--aqua), var(--amber));
}

.back-to-top {
  position: fixed;
  right: clamp(12px, 3vw, 28px);
  bottom: clamp(12px, 3vw, 28px);
  z-index: 110;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 15px;
  border: 1px solid var(--line);
  background: rgba(16, 29, 51, .94);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity .24s var(--ease), transform .24s var(--ease), visibility .24s var(--ease), border-color .24s var(--ease), color .24s var(--ease);
}

.back-to-top[data-visible] {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.back-to-top:hover {
  border-color: var(--aqua);
  color: var(--aqua);
}

.back-to-top__arrow { color: var(--amber); }

/* ---------- 14. 显现动效协议 ---------- */
html[data-js="on"] [data-reveal] {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity .55s var(--ease), transform .55s var(--ease);
}

html[data-js="on"] [data-reveal][data-revealed] {
  opacity: 1;
  transform: none;
}

/* ---------- 15. 响应式 ---------- */
@media (max-width: 1100px) {
  .brand__subline { display: none; }
  .header-upper__inner { grid-template-columns: auto minmax(0, 1fr) auto; }
}

@media (max-width: 960px) {
  .header-upper__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 10px 16px;
    padding-block: 12px 10px;
  }

  .brand { grid-column: 1; }
  .nav-toggle { grid-column: 2; display: inline-flex; }
  .utility-nav {
    grid-column: 1 / -1;
    justify-self: start;
    gap: 18px;
    padding-top: 10px;
    border-top: 1px solid var(--line);
  }

  .site-nav { display: none; }

  .site-nav[data-open] {
    display: block;
    max-height: min(72vh, 540px);
    overflow-y: auto;
  }

  .site-nav__list {
    flex-direction: column;
    gap: 0;
    overflow: visible;
  }

  .site-nav__item { width: 100%; }
  .site-nav__item + .site-nav__item { border-top: 1px solid var(--line); }

  .site-nav__link {
    padding: 14px 6px;
    border-bottom: 0;
    font-size: 15px;
  }

  .site-nav__link[aria-current="page"] {
    box-shadow: inset 2px 0 0 var(--aqua);
    border-bottom-color: transparent;
  }

  .footer__inner { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
  .footer__col--brand { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  [id] { scroll-margin-top: 108px; }

  .section__note { margin-left: 0; max-width: none; }
  .index-list__item { grid-template-columns: auto minmax(0, 1fr); }
  .index-list__meta { grid-column: 2; white-space: normal; }
  .footer__inner { grid-template-columns: minmax(0, 1fr); padding-block: 36px; }
  .footer__list { grid-template-columns: minmax(0, 1fr); }
  .footer__base-inner { flex-direction: column; align-items: flex-start; }
  .back-to-top { font-size: 10.5px; padding: 9px 12px; }
}

/* ---------- 16. 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;
  }

  .header-scan::after { content: none; animation: none; }

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