/* ==========================================================================
   趣体育官方 · 共享样式表 /assets/site.css
   夜灯球场 + 卷宗档案室 · 非对称展览画册式版式
   ========================================================================== */

/* ---------- 1. 设计变量 ---------- */
:root {
  --blue: #0B1B3A;
  --blue-deep: #07090D;
  --paper: #F4F1EA;
  --orange: #FF5A1F;
  --violet: #7B4DFF;
  --pitch: #1FA463;
  --amber: #FFB020;
  --slate: #5B6B84;
  --steel: #D9E2F0;
  --panel-a: #101A2E;
  --panel-b: #1D2B4A;

  --line: rgba(91, 107, 132, .28);
  --line-dark: rgba(217, 226, 240, .16);
  --line-darker: rgba(217, 226, 240, .28);

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

  --wrap: 1320px;
  --gutter: clamp(16px, 4vw, 40px);
  --nav-h: 64px;
  --r-soft: 2px 18px 2px 18px;
  --r-soft-sm: 2px 12px 2px 12px;
}

/* ---------- 2. 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, li, figure, figcaption, blockquote, dl, dd {
  margin: 0;
  padding: 0;
}

ul, ol { list-style: none; }

body {
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.75;
  color: var(--blue-deep);
  background: var(--paper);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

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

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

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

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

h1, h2, h3, h4 {
  font-family: var(--font-head);
  font-weight: 800;
  line-height: 1.05;
  letter-spacing: .01em;
  text-wrap: balance;
}

b, strong { font-weight: 700; }

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

.skip-link {
  position: fixed;
  left: 16px;
  top: 12px;
  z-index: 200;
  padding: 11px 18px;
  background: var(--orange);
  color: var(--blue-deep);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: .04em;
  border-radius: 0 0 12px 12px;
  transform: translateY(-260%);
  transition: transform .2s ease;
}

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

/* ---------- 3. 通用排版与工具 ---------- */
.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: .02em;
}

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: clamp(16px, 2.2vw, 30px);
}

.col-index { grid-column: span 2; }
.col-main  { grid-column: span 7; }
.col-aside { grid-column: span 3; }
.w-12      { grid-column: 1 / -1; }

.col-sticky {
  position: sticky;
  top: calc(var(--nav-h) + 24px);
  align-self: start;
}

.section { padding-block: clamp(40px, 6vw, 86px); }
.section--tight { padding-block: clamp(24px, 3vw, 46px); }

.band {
  background: var(--blue);
  color: #D5DEEE;
}
.band--steel { background: var(--steel); color: var(--blue-deep); }
.band--pitch { background: linear-gradient(118deg, var(--blue) 0%, #123F31 100%); color: #DCE9E1; }
.band--ink   { background: var(--blue-deep); color: #D5DEEE; }

.prose {
  max-width: 68ch;
  font-size: 17px;
  line-height: 1.75;
  color: var(--blue-deep);
}

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

.prose h2 {
  font-size: clamp(26px, 3vw, 38px);
  margin-top: 1.6em;
  margin-bottom: .6em;
  color: var(--blue);
}

.prose h3 {
  font-size: clamp(19px, 1.6vw, 24px);
  margin-top: 1.4em;
  margin-bottom: .5em;
}

.prose ul, .prose ol {
  margin-top: .9em;
  display: grid;
  gap: .5em;
}

.prose li {
  padding-left: 20px;
  position: relative;
}

.prose li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .72em;
  width: 9px;
  height: 2px;
  background: var(--orange);
}

.prose strong { color: var(--blue); }

.kicker {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--slate);
}

.v-note {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .22em;
  color: var(--slate);
}

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: 16px 28px;
  padding-bottom: 14px;
  margin-bottom: clamp(20px, 2.6vw, 34px);
  border-bottom: 2px solid var(--blue-deep);
}

.section-head__title {
  font-size: clamp(28px, 3.4vw, 44px);
  color: var(--blue);
}

.section-head__note {
  font-size: 13px;
  letter-spacing: .06em;
  color: var(--slate);
}

.rule-band {
  position: relative;
  overflow: hidden;
  background: var(--blue);
  color: var(--paper);
}

.rule-band::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(115deg, rgba(244, 241, 234, .05) 0 2px, transparent 2px 15px);
  pointer-events: none;
}

.rule-band__inner {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px 26px;
  padding-block: clamp(18px, 2.4vw, 28px);
}

/* ---------- 4. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 22px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 15px;
  line-height: 1;
  letter-spacing: .05em;
  white-space: nowrap;
  border: 1px solid transparent;
  border-radius: 2px;
  transition: background-color .2s ease, color .2s ease, border-color .2s ease, transform .2s ease;
}

.btn--cta {
  background: var(--orange);
  color: var(--blue-deep);
  clip-path: polygon(0 0, 100% 0, 100% 100%, 12px 100%, 0 calc(100% - 12px));
  padding-right: 24px;
}

.btn--cta:hover { background: #FF7A46; transform: translateY(-2px); }

.btn--ghost {
  border-color: rgba(217, 226, 240, .45);
  color: var(--paper);
  border-radius: var(--r-soft-sm);
}

.btn--ghost:hover {
  border-color: var(--orange);
  color: var(--orange);
  transform: translateY(-2px);
}

.btn--line {
  border-color: var(--blue);
  color: var(--blue);
  border-radius: var(--r-soft-sm);
}

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

/* ---------- 5. 标签 / 数据块 / 表格 ---------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 11px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .08em;
  color: var(--slate);
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(217, 226, 240, .35);
}

.tag--orange { color: #B33600; border-color: rgba(255, 90, 31, .45); background: rgba(255, 90, 31, .12); }
.tag--violet { color: #4A2BB0; border-color: rgba(123, 77, 255, .4);  background: rgba(123, 77, 255, .12); }
.tag--pitch  { color: #0F6B40; border-color: rgba(31, 164, 99, .4);  background: rgba(31, 164, 99, .13); }
.tag--amber  { color: #8A5A00; border-color: rgba(255, 176, 32, .5); background: rgba(255, 176, 32, .16); }

.stat {
  display: grid;
  gap: 6px;
}

.stat__value {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: clamp(28px, 3.2vw, 44px);
  line-height: 1;
  color: var(--blue);
  font-variant-numeric: tabular-nums;
}

.stat__value--hot { color: var(--orange); }
.stat__label {
  font-size: 13px;
  letter-spacing: .07em;
  color: var(--slate);
}

.data-table {
  width: 100%;
  font-size: 14px;
  line-height: 1.6;
}

.data-table caption {
  caption-side: top;
  text-align: left;
  padding-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .12em;
  color: var(--slate);
}

.data-table th {
  padding: 11px 12px;
  text-align: left;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .1em;
  text-transform: uppercase;
  color: var(--slate);
  border-bottom: 2px solid var(--blue-deep);
  white-space: nowrap;
}

.data-table td {
  padding: 12px;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

.data-table td.num {
  font-family: var(--font-mono);
  text-align: right;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.data-table tbody tr:nth-child(even) { background: rgba(217, 226, 240, .4); }
.data-table tbody tr:hover { background: rgba(255, 90, 31, .07); }

/* ---------- 6. 图片容器（页面阶段放置图片） ---------- */
.media-frame {
  position: relative;
  overflow: hidden;
  border-radius: 26px 6px 26px 6px;
  background: linear-gradient(140deg, var(--panel-a), var(--panel-b));
  isolation: isolate;
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  aspect-ratio: 16 / 10;
}

.media-frame--tall img { aspect-ratio: 3 / 4; }
.media-frame--band img { aspect-ratio: 21 / 9; }
.media-frame--square img { aspect-ratio: 1 / 1; }

.media-frame--pitch {
  background-image:
    repeating-linear-gradient(90deg, rgba(31, 164, 99, .22) 0 26px, rgba(31, 164, 99, .08) 26px 52px),
    linear-gradient(140deg, var(--panel-a), #123F31);
}

.media-frame__cap {
  position: absolute;
  left: 14px;
  bottom: 12px;
  z-index: 2;
  padding: 7px 11px;
  border-radius: 6px;
  background: rgba(7, 9, 13, .74);
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .08em;
}

.media-frame--ph {
  display: grid;
  place-items: center;
  background-image:
    radial-gradient(rgba(244, 241, 234, .16) 1.2px, transparent 1.2px),
    linear-gradient(140deg, var(--panel-a), var(--panel-b));
  background-size: 14px 14px, auto;
}

.media-frame--ph::after { content: ""; aspect-ratio: 16 / 10; }

.media-frame--ph span {
  position: absolute;
  z-index: 2;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: rgba(244, 241, 234, .62);
}

/* ---------- 7. 面包屑 ---------- */
.crumbs { margin-top: clamp(18px, 2vw, 28px); }

.crumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .08em;
  color: var(--slate);
}

.crumbs__list li { display: inline-flex; align-items: center; gap: 8px; }

.crumbs__list li + li::before {
  content: "/";
  color: var(--steel);
}

.crumbs__list a:hover { color: var(--orange); }
.crumbs__list [aria-current="page"] { color: var(--blue-deep); }

/* ---------- 8. 头部 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: var(--blue);
  color: var(--paper);
}

/* 8.1 品牌说明层 */
.brand-rail {
  position: relative;
  overflow: hidden;
  max-height: 64px;
  background: var(--blue-deep);
  background-image: radial-gradient(rgba(244, 241, 234, .08) 1px, transparent 1px);
  background-size: 12px 12px;
  border-bottom: 1px solid var(--line-dark);
  transition: max-height .34s ease, opacity .22s ease, border-bottom-color .34s ease;
}

.site-header[data-collapsed] .brand-rail {
  max-height: 0;
  opacity: 0;
  border-bottom-color: transparent;
}

.brand-rail__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 40px;
}

.brand-rail__pitch {
  font-size: 13px;
  letter-spacing: .06em;
  color: #A9B9D2;
}

.brand-rail__meta {
  display: flex;
  align-items: center;
  gap: 18px;
  font-size: 12px;
  letter-spacing: .08em;
  color: #8FA3C2;
  white-space: nowrap;
}

.brand-rail__round b {
  color: var(--orange);
  font-weight: 700;
}

.brand-rail__link {
  color: var(--paper);
  border-bottom: 1px solid rgba(255, 90, 31, .6);
  padding-bottom: 2px;
  transition: color .2s ease, border-color .2s ease;
}

.brand-rail__link:hover {
  color: var(--orange);
  border-bottom-color: var(--orange);
}

/* 8.2 栏目层 */
.nav-rail {
  position: relative;
  background: var(--blue);
  border-bottom: 1px solid var(--line-dark);
}

.nav-rail__inner {
  display: flex;
  align-items: center;
  gap: clamp(12px, 1.8vw, 26px);
  min-height: var(--nav-h);
}

.index-toggle {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 9px 13px;
  border: 1px solid var(--line-darker);
  border-radius: var(--r-soft-sm);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .12em;
  color: #C8D5E8;
  transition: color .2s ease, border-color .2s ease, background-color .2s ease;
}

.index-toggle:hover {
  color: var(--orange);
  border-color: var(--orange);
}

.index-toggle__bars {
  display: grid;
  gap: 3px;
  width: 14px;
}

.index-toggle__bars i {
  display: block;
  height: 2px;
  background: currentColor;
}

.index-toggle__bars i:nth-child(2) { width: 72%; }
.index-toggle__bars i:nth-child(3) { width: 44%; }

.index-toggle[aria-expanded="true"] {
  background: var(--orange);
  border-color: var(--orange);
  color: var(--blue-deep);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-right: auto;
}

.brand__mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  flex: none;
  background: var(--orange);
  color: var(--blue-deep);
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 18px;
  line-height: 1;
  border-radius: var(--r-soft-sm);
}

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

.brand__name {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 17px;
  line-height: 1;
  letter-spacing: .05em;
  color: var(--paper);
}

.brand__sub {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 600;
  line-height: 1;
  letter-spacing: .22em;
  color: #8FA3C2;
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(6px, 1.3vw, 20px);
}

.site-nav__list a {
  position: relative;
  display: block;
  padding: 8px 4px;
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 15px;
  line-height: 1;
  letter-spacing: .02em;
  color: #D5DEEE;
  transition: color .2s ease;
}

.site-nav__list a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--orange);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform .22s ease;
}

.site-nav__list a:hover { color: #FFFFFF; }
.site-nav__list a:hover::after { transform: scaleX(1); }

.site-nav__list a[aria-current="page"] { color: var(--orange); }
.site-nav__list a[aria-current="page"]::after { transform: scaleX(1); }

.nav-rail__cta { flex: none; }

.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 9px 13px;
  border: 1px solid var(--line-darker);
  border-radius: var(--r-soft-sm);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .1em;
  color: #D5DEEE;
}

.nav-toggle__box {
  display: grid;
  gap: 4px;
  width: 16px;
}

.nav-toggle__box i {
  display: block;
  height: 2px;
  background: currentColor;
  transition: transform .22s ease;
}

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

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

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

.scroll-progress {
  position: absolute;
  left: 0;
  bottom: -1px;
  z-index: 3;
  display: block;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--violet), var(--orange));
}

/* 8.3 卷宗索引卡阵 */
.index-band {
  display: none;
  background: #0E1730;
  border-bottom: 1px solid var(--line-dark);
}

.index-band[data-open] {
  display: block;
  animation: bandIn .28s ease-out both;
}

.index-band__grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  padding-block: 20px 24px;
}

.index-card {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 4px 13px;
  padding: 15px 17px;
  background: rgba(217, 226, 240, .05);
  border: 1px solid rgba(217, 226, 240, .12);
  border-radius: var(--r-soft);
  transition: background-color .22s ease, border-color .22s ease, transform .22s ease;
}

.index-card:hover {
  background: rgba(255, 90, 31, .13);
  border-color: rgba(255, 90, 31, .5);
  transform: translateY(-3px);
}

.index-card__no {
  grid-row: span 2;
  padding-top: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .1em;
  color: var(--orange);
}

.index-card__label {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.2;
  color: var(--paper);
}

.index-card__note {
  grid-column: 2;
  font-size: 12px;
  line-height: 1.5;
  letter-spacing: .04em;
  color: #8FA3C2;
}

@keyframes bandIn {
  from { opacity: 0; transform: translateY(-10px); }
  to   { opacity: 1; transform: none; }
}

@keyframes navIn {
  from { opacity: 0; transform: translateY(-8px); }
  to   { opacity: 1; transform: none; }
}

/* ---------- 9. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(48px, 7vw, 100px);
  background: var(--blue);
  background-image: linear-gradient(180deg, var(--panel-a) 0%, var(--blue) 55%, var(--panel-b) 100%);
  color: #D5DEEE;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 3px;
  background: linear-gradient(90deg, var(--orange) 0%, var(--violet) 46%, var(--pitch) 100%);
}

.site-footer__inner {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 2fr) minmax(0, 1.15fr);
  gap: clamp(28px, 4vw, 60px);
  padding-block: clamp(38px, 5vw, 68px) clamp(26px, 3vw, 40px);
}

.site-footer__brand {
  display: grid;
  align-content: start;
  gap: 12px;
}

.footer-brand {
  font-family: var(--font-head);
  font-weight: 800;
  font-size: 24px;
  line-height: 1.1;
  letter-spacing: .05em;
  color: var(--paper);
}

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

.footer-brand__line {
  font-size: 13px;
  letter-spacing: .05em;
  color: #9FB0CB;
}

.footer-brand__stat {
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--orange);
}

.site-footer__brand .btn { justify-self: start; margin-top: 6px; }

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.footer-col__title {
  margin-bottom: 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .16em;
  color: #8FA3C2;
}

.footer-col__list {
  display: grid;
  gap: 11px;
}

.footer-col__list a {
  font-size: 14px;
  letter-spacing: .03em;
  color: #D5DEEE;
  border-bottom: 1px solid transparent;
  transition: color .2s ease, border-color .2s ease;
}

.footer-col__list a:hover {
  color: var(--orange);
  border-bottom-color: rgba(255, 90, 31, .55);
}

.footer-contact {
  display: grid;
  align-content: start;
  gap: 14px;
}

.footer-contact__row { display: grid; gap: 3px; }

.footer-contact__k {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .16em;
  color: #8FA3C2;
}

.footer-contact__v {
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.6;
  color: #E4EAF4;
  word-break: break-word;
}

.footer-contact__hint {
  padding-top: 12px;
  border-top: 1px dashed var(--line-dark);
  font-size: 12px;
  line-height: 1.7;
  color: #8FA3C2;
}

.site-footer__base {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 10px 22px;
  padding-block: 18px 26px;
  border-top: 1px solid var(--line-dark);
  font-size: 12px;
  letter-spacing: .06em;
  color: #8FA3C2;
}

.footer-base__links {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-base__links a { transition: color .2s ease; }
.footer-base__links a:hover { color: var(--orange); }

/* ---------- 10. 返回顶部 ---------- */
.to-top {
  position: fixed;
  right: clamp(14px, 3vw, 32px);
  bottom: clamp(14px, 3vw, 32px);
  z-index: 90;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 17px;
  background: var(--orange);
  color: var(--blue-deep);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 14px;
  line-height: 1;
  letter-spacing: .06em;
  border-radius: var(--r-soft-sm);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: opacity .24s ease, transform .24s ease, visibility .24s ease, background-color .2s ease;
}

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

.to-top:hover { background: #FF7A46; }

.to-top__arrow { font-family: var(--font-mono); font-size: 15px; }

/* ---------- 11. 显现与目录 ---------- */
.js .reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .55s ease, transform .55s ease;
}

.js .reveal.is-in {
  opacity: 1;
  transform: none;
}

[data-toc] a[aria-current="location"] {
  color: var(--orange);
  font-weight: 700;
}

/* ---------- 12. 响应式 ---------- */
@media (max-width: 1180px) {
  .nav-rail__cta { padding: 12px 16px; font-size: 14px; }
}

@media (max-width: 1023px) {
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .col-index { grid-column: span 6; }
  .col-main  { grid-column: span 6; }
  .col-aside { grid-column: span 6; }

  .col-sticky { position: static; }

  .index-toggle { display: none; }
  .index-band { display: none !important; }

  .nav-toggle { display: inline-flex; }
  .nav-rail__cta { display: none; }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    display: none;
    background: var(--blue);
    border-bottom: 1px solid var(--line-dark);
    box-shadow: 0 26px 44px rgba(7, 9, 13, .42);
  }

  .site-nav[data-open] {
    display: block;
    max-height: calc(100vh - var(--nav-h));
    overflow-y: auto;
    animation: navIn .24s ease-out both;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px var(--gutter) 20px;
  }

  .site-nav__list a {
    padding: 15px 2px;
    font-size: 17px;
    border-bottom: 1px solid var(--line-dark);
  }

  .site-nav__list a::after { display: none; }

  .site-footer__inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 34px;
  }

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

@media (max-width: 720px) {
  body { font-size: 16px; }

  .brand-rail__pitch { display: none; }
  .brand-rail__inner { justify-content: flex-end; }

  .brand__sub { display: none; }

  .index-band__grid { grid-template-columns: 1fr; }

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

  .site-footer__base {
    flex-direction: column;
    align-items: flex-start;
  }

  .to-top { padding: 11px 14px; }
  .to-top span:last-child { display: none; }
}

@media (max-width: 480px) {
  .footer-cols { grid-template-columns: minmax(0, 1fr); }
  .nav-toggle__label { display: none; }
}

/* ---------- 13. 无障碍与动效偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }

  .js .reveal { opacity: 1; transform: none; }
  .to-top { transform: none; }
  .skip-link { transition: none; }
}