/* ==========================================================================
   BOB看台 · 共享样式表 /assets/site.css
   夜间赛道边 · 目录型内容地图 · 粗边框硬投影
   ========================================================================== */

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

html, body, h1, h2, h3, h4, h5, h6, p, ul, ol, li, figure, figcaption,
blockquote, dl, dd, dt, nav, header, footer, section, article, aside { margin: 0; padding: 0; }

ul, ol { list-style: none; }

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

body { min-height: 100%; }

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

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

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

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

summary { list-style: none; }
summary::-webkit-details-marker { display: none; }

/* 2. 设计变量 ------------------------------------------------------------- */
:root {
  /* 色彩：沥青深灰为底，信号黄为唯一高饱和锚点 */
  --asphalt-900: #0E1013;
  --asphalt-800: #171A1F;
  --grid-gray: #2B3138;
  --pit-white: #F4F5F2;
  --signal-yellow: #F6C500;
  --highlight-yellow: #FFE07A;
  --card-red: #E23B3B;
  --ruling-yellow: #EDB02A;
  --mist-cyan: #7FB6B2;
  --deep-ink: #05070A;

  /* 字体 */
  --font-display: Oswald, "Barlow Condensed", "PingFang SC", "Noto Sans SC", sans-serif;
  --font-index: "JetBrains Mono", "Roboto Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  --font-body: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;

  /* 字号尺度：标题与索引形成 6:1 落差 */
  --fs-hero: clamp(56px, 11vw, 172px);
  --fs-h1: clamp(40px, 6.4vw, 96px);
  --fs-h2: clamp(26px, 3.2vw, 50px);
  --fs-h3: clamp(19px, 2.1vw, 28px);
  --fs-index: 12px;

  /* 结构 */
  --wrap-max: 1240px;
  --gutter: clamp(16px, 4vw, 40px);
  --line: 2px;
  --shadow-hard: 6px 6px 0 rgba(5, 7, 10, 0.85);
  --shadow-hard-lg: 10px 10px 0 rgba(5, 7, 10, 0.9);
  --sticky-offset: 138px;
}

/* 3. 中文基础排版 --------------------------------------------------------- */
body {
  background: var(--asphalt-900);
  color: var(--pit-white);
  font-family: var(--font-body);
  font-size: clamp(16px, 0.35vw + 15px, 18px);
  line-height: 1.75;
  font-variant-numeric: tabular-nums;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 400;
  line-height: 1.08;
  letter-spacing: 0.02em;
}

h1 { font-size: var(--fs-h1); font-weight: 300; }
h2 { font-size: var(--fs-h2); font-weight: 300; }
h3 { font-size: var(--fs-h3); }

strong { font-weight: 600; }

::selection {
  background: var(--signal-yellow);
  color: var(--asphalt-900);
}

:focus-visible {
  outline: 3px solid var(--signal-yellow);
  outline-offset: 3px;
}

/* 4. 布局容器与网格 ------------------------------------------------------- */
.wrap {
  width: 100%;
  max-width: var(--wrap-max);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.grid {
  display: grid;
  gap: clamp(18px, 2.4vw, 32px);
}

.grid--8-4 {
  grid-template-columns: minmax(0, 1.95fr) minmax(0, 1fr);
  align-items: start;
}

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

.stack { display: grid; gap: 14px; }
.stack--loose { gap: clamp(20px, 3vw, 34px); }

.section { padding-block: clamp(36px, 6vw, 88px); }
.section--tight { padding-block: clamp(22px, 3vw, 44px); }

.section--board {
  background: var(--asphalt-800);
  border-top: var(--line) solid var(--grid-gray);
  border-bottom: var(--line) solid var(--grid-gray);
}

.section__head {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: clamp(18px, 3vw, 34px);
}

.section__title { font-size: var(--fs-h2); font-weight: 300; }

.section__note {
  font-family: var(--font-index);
  font-size: var(--fs-index);
  letter-spacing: 0.08em;
  color: var(--mist-cyan);
}

/* 赛道线 */
.rule {
  height: var(--line);
  border: 0;
  background-image: repeating-linear-gradient(90deg, var(--grid-gray) 0 24px, transparent 24px 42px);
}

.rule--solid { background-image: none; background-color: var(--grid-gray); }

/* 5. 文字构件 ------------------------------------------------------------- */
.display {
  font-family: var(--font-display);
  font-size: var(--fs-hero);
  font-weight: 300;
  line-height: 0.92;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.eyebrow {
  font-family: var(--font-index);
  font-size: var(--fs-index);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--signal-yellow);
}

.lede {
  font-size: clamp(17px, 1.3vw, 20px);
  line-height: 1.72;
  color: rgba(244, 245, 242, 0.86);
  max-width: 38em;
}

.prose { max-width: 38em; }
.prose > * + * { margin-top: 1.05em; }

.prose h2 { font-size: var(--fs-h2); margin-top: 1.6em; }
.prose h3 { margin-top: 1.4em; }

.prose ul li {
  position: relative;
  padding-left: 20px;
  margin-top: 0.45em;
}

.prose ul li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.68em;
  width: 8px;
  height: 8px;
  background: var(--signal-yellow);
}

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

/* 6. 按钮 ----------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 9px 14px;
  border: var(--line) solid var(--pit-white);
  background: transparent;
  color: var(--pit-white);
  font-family: var(--font-index);
  font-size: var(--fs-index);
  letter-spacing: 0.06em;
  line-height: 1.2;
  white-space: nowrap;
  transition: background-color 0.16s ease, color 0.16s ease, border-color 0.16s ease;
}

.btn:hover { background: var(--pit-white); color: var(--asphalt-900); }

.btn--primary {
  background: var(--signal-yellow);
  border-color: var(--signal-yellow);
  color: var(--asphalt-900);
}

.btn--primary:hover {
  background: var(--highlight-yellow);
  border-color: var(--highlight-yellow);
  color: var(--asphalt-900);
}

.btn--ghost {
  border-color: var(--grid-gray);
  color: var(--mist-cyan);
}

.btn--ghost:hover {
  background: var(--asphalt-900);
  border-color: var(--mist-cyan);
  color: var(--pit-white);
}

.btn--block { width: 100%; }

/* 7. 跳转链接 ------------------------------------------------------------- */
.skip-link {
  position: absolute;
  top: -140px;
  left: var(--gutter);
  z-index: 200;
  display: inline-block;
  padding: 10px 16px;
  background: var(--signal-yellow);
  color: var(--asphalt-900);
  font-family: var(--font-index);
  font-size: var(--fs-index);
  letter-spacing: 0.08em;
  border: var(--line) solid var(--deep-ink);
  transition: top 0.16s ease;
}

.skip-link:focus { top: 10px; }

/* 8. 站点头部 ------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 120;
  background: var(--asphalt-900);
  border-bottom: var(--line) solid var(--grid-gray);
}

.progress-rail {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 3px;
  background: var(--grid-gray);
  overflow: hidden;
  z-index: 2;
}

.progress-rail__bar {
  display: block;
  width: 100%;
  height: 100%;
  background: var(--signal-yellow);
  transform: scaleX(0);
  transform-origin: left center;
}

.header-strip {
  background-color: var(--deep-ink);
  background-image: repeating-linear-gradient(
    135deg,
    rgba(244, 245, 242, 0.045) 0 2px,
    rgba(244, 245, 242, 0) 2px 9px
  );
  border-bottom: var(--line) solid var(--grid-gray);
}

.header-strip__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: clamp(12px, 2vw, 28px);
  min-height: 64px;
  padding-block: 8px;
}

/* 品牌 */
.brand { display: inline-flex; align-items: center; gap: 12px; }

.brand__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 6px 8px;
  background: var(--signal-yellow);
  color: var(--asphalt-900);
  font-family: var(--font-index);
  font-size: var(--fs-index);
  font-weight: 700;
  letter-spacing: 0.1em;
  border: var(--line) solid var(--signal-yellow);
  box-shadow: 4px 4px 0 rgba(246, 197, 0, 0.22);
}

.brand__text { display: flex; flex-direction: column; line-height: 1.15; }

.brand__name {
  font-family: var(--font-display);
  font-size: 20px;
  letter-spacing: 0.06em;
  color: var(--pit-white);
}

.brand__line {
  font-family: var(--font-index);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist-cyan);
}

/* 状态点提示 */
.status-hint {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 14px;
  font-family: var(--font-index);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist-cyan);
}

.status-hint__item { display: inline-flex; align-items: center; gap: 6px; }
.status-hint__item--muted { opacity: 0.72; }

.dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  background: var(--grid-gray);
}

.dot--red { background: var(--card-red); }
.dot--yellow { background: var(--ruling-yellow); }

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: var(--line) solid var(--grid-gray);
  color: var(--pit-white);
  font-family: var(--font-index);
  font-size: 11px;
  letter-spacing: 0.08em;
  transition: border-color 0.16s ease, color 0.16s ease;
}

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

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 18px;
  height: 10px;
  border-top: var(--line) solid currentColor;
  border-bottom: var(--line) solid currentColor;
}

.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: var(--line);
  margin-top: -1px;
  background: currentColor;
}

/* 命令栏索引 */
.site-nav {
  background: var(--asphalt-800);
  border-bottom: var(--line) solid var(--grid-gray);
}

.site-nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 14px;
  padding-block: 10px;
}

.site-nav__list {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 2px;
}

.site-nav__item { display: block; min-width: 0; }

.site-nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 7px 12px;
  border: var(--line) solid transparent;
  color: var(--pit-white);
  font-size: 15px;
  line-height: 1.4;
  transition: background-color 0.16s ease, color 0.16s ease, border-color 0.16s ease;
}

.site-nav__num {
  font-family: var(--font-index);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist-cyan);
}

.site-nav__link:hover {
  background: var(--asphalt-900);
  border-color: var(--grid-gray);
}

.site-nav__link:hover .site-nav__num { color: var(--signal-yellow); }

.site-nav__link[aria-current="page"] {
  background: var(--signal-yellow);
  border-color: var(--signal-yellow);
  color: var(--asphalt-900);
}

.site-nav__link[aria-current="page"] .site-nav__num { color: var(--asphalt-900); }

.site-nav__actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

/* 9. 站点页脚 ------------------------------------------------------------- */
.site-footer {
  margin-top: clamp(48px, 8vw, 120px);
  background-color: var(--deep-ink);
  background-image: repeating-linear-gradient(
    135deg,
    rgba(244, 245, 242, 0.032) 0 2px,
    rgba(244, 245, 242, 0) 2px 9px
  );
  border-top: var(--line) solid var(--grid-gray);
  color: var(--pit-white);
}

.footer-top {
  display: grid;
  grid-template-columns:
    minmax(200px, 1.45fr)
    repeat(3, minmax(96px, 0.75fr))
    minmax(190px, 1.25fr);
  gap: clamp(20px, 3vw, 40px);
  padding-block: clamp(36px, 6vw, 72px) clamp(26px, 4vw, 48px);
}

.footer-brand__link { display: inline-flex; align-items: center; gap: 10px; }

.footer-brand__mark {
  display: inline-flex;
  align-items: center;
  padding: 5px 8px;
  background: var(--signal-yellow);
  color: var(--asphalt-900);
  font-family: var(--font-index);
  font-size: var(--fs-index);
  font-weight: 700;
  letter-spacing: 0.1em;
}

.footer-brand__name {
  font-family: var(--font-display);
  font-size: 20px;
  letter-spacing: 0.06em;
}

.footer-brand__line {
  margin-top: 12px;
  font-family: var(--font-index);
  font-size: var(--fs-index);
  letter-spacing: 0.08em;
  color: var(--signal-yellow);
}

.footer-brand__note {
  margin-top: 10px;
  max-width: 32em;
  font-size: 14px;
  line-height: 1.7;
  color: rgba(244, 245, 242, 0.68);
}

.footer-col { min-width: 0; }
.footer-contact { min-width: 0; }

.footer-col__title {
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: var(--line) solid var(--grid-gray);
  font-family: var(--font-index);
  font-size: var(--fs-index);
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--mist-cyan);
}

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

.footer-link {
  display: inline-block;
  font-size: 15px;
  color: var(--pit-white);
  border-bottom: var(--line) solid transparent;
  transition: color 0.16s ease, border-color 0.16s ease;
}

.footer-link:hover {
  color: var(--signal-yellow);
  border-bottom-color: var(--signal-yellow);
}

.footer-contact__row { display: grid; gap: 2px; }

.footer-contact__label {
  font-family: var(--font-index);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist-cyan);
}

.footer-contact__value {
  font-size: 14px;
  line-height: 1.6;
  color: var(--pit-white);
  word-break: break-word;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  padding-block: 18px;
  border-top: var(--line) solid var(--grid-gray);
  font-family: var(--font-index);
  font-size: var(--fs-index);
  letter-spacing: 0.06em;
  color: rgba(244, 245, 242, 0.7);
}

.footer-bottom__copy,
.footer-bottom__legal { max-width: none; }

/* 10. 面包屑 --------------------------------------------------------------- */
.breadcrumbs {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  padding-block: 18px;
  font-family: var(--font-index);
  font-size: var(--fs-index);
  letter-spacing: 0.08em;
  color: var(--mist-cyan);
}

.breadcrumbs__link {
  color: var(--pit-white);
  border-bottom: var(--line) solid var(--grid-gray);
  transition: color 0.16s ease, border-color 0.16s ease;
}

.breadcrumbs__link:hover {
  color: var(--signal-yellow);
  border-bottom-color: var(--signal-yellow);
}

.breadcrumbs__sep { color: var(--grid-gray); }
.breadcrumbs__current { color: var(--signal-yellow); }

/* 11. 卡片 ---------------------------------------------------------------- */
.card {
  position: relative;
  display: block;
  padding: clamp(16px, 2vw, 26px);
  background: var(--asphalt-800);
  border: var(--line) solid var(--grid-gray);
  box-shadow: var(--shadow-hard);
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hard-lg);
  border-color: var(--signal-yellow);
}

.card__index {
  font-family: var(--font-index);
  font-size: var(--fs-index);
  letter-spacing: 0.08em;
  color: var(--signal-yellow);
}

.card__title {
  margin-top: 8px;
  font-family: var(--font-display);
  font-size: var(--fs-h3);
  font-weight: 400;
}

.card__meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 10px;
  font-family: var(--font-index);
  font-size: var(--fs-index);
  letter-spacing: 0.08em;
  color: var(--mist-cyan);
}

.card__text {
  margin-top: 10px;
  font-size: 15px;
  line-height: 1.7;
  color: rgba(244, 245, 242, 0.8);
}

.card--offset { transform: translateY(18px); }
.card--offset:hover { transform: translateY(14px); }

/* 12. 标签与图例 ---------------------------------------------------------- */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 8px;
  border: var(--line) solid var(--grid-gray);
  background: var(--asphalt-900);
  font-family: var(--font-index);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--pit-white);
  line-height: 1.5;
}

.tag--red { background: var(--card-red); border-color: var(--card-red); color: #FFFFFF; }
.tag--yellow { background: var(--ruling-yellow); border-color: var(--ruling-yellow); color: var(--asphalt-900); }
.tag--signal { background: var(--signal-yellow); border-color: var(--signal-yellow); color: var(--asphalt-900); }
.tag--cyan { border-color: var(--mist-cyan); color: var(--mist-cyan); }

.legend {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  font-family: var(--font-index);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--mist-cyan);
}

.legend__item { display: inline-flex; align-items: center; gap: 6px; }

/* 13. 数据面板 ------------------------------------------------------------ */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: var(--line);
  background: var(--grid-gray);
  border: var(--line) solid var(--grid-gray);
}

.stat { padding: 16px; background: var(--asphalt-900); }

.stat__value {
  font-family: var(--font-index);
  font-size: clamp(24px, 3vw, 36px);
  line-height: 1.1;
  letter-spacing: 0.04em;
  color: var(--signal-yellow);
}

.stat__label {
  margin-top: 6px;
  font-family: var(--font-index);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist-cyan);
}

/* 14. 侧栏面板 ------------------------------------------------------------ */
.panel {
  padding: 16px;
  background: var(--asphalt-800);
  border: var(--line) solid var(--grid-gray);
}

.panel + .panel { margin-top: 16px; }

.panel__title {
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: var(--line) solid var(--grid-gray);
  font-family: var(--font-index);
  font-size: var(--fs-index);
  font-weight: 400;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--signal-yellow);
}

.panel--sticky {
  position: sticky;
  top: var(--sticky-offset);
}

/* 15. 折叠面板 ------------------------------------------------------------ */
.accordion {
  border: var(--line) solid var(--grid-gray);
  background: var(--asphalt-800);
}

.accordion__item + .accordion__item { border-top: var(--line) solid var(--grid-gray); }

.accordion__trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  width: 100%;
  padding: 16px;
  text-align: left;
  font-size: 16px;
  cursor: pointer;
}

.accordion__trigger::after {
  content: "+";
  flex: none;
  font-family: var(--font-index);
  color: var(--signal-yellow);
}

.accordion__item[open] .accordion__trigger::after { content: "–"; }

.accordion__panel {
  padding: 0 16px 16px;
  font-size: 15px;
  line-height: 1.75;
  color: rgba(244, 245, 242, 0.82);
  max-width: 38em;
}

/* 16. 章节索引 ------------------------------------------------------------ */
.section-index {
  display: grid;
  gap: var(--line);
  background: var(--grid-gray);
  border: var(--line) solid var(--grid-gray);
}

.section-index__link {
  display: flex;
  align-items: baseline;
  gap: 12px;
  padding: 12px 14px;
  background: var(--asphalt-900);
  font-size: 15px;
  transition: background-color 0.16s ease, color 0.16s ease;
}

.section-index__num {
  font-family: var(--font-index);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist-cyan);
}

.section-index__link:hover { background: var(--asphalt-800); }

.section-index__link[data-active="true"] {
  background: var(--asphalt-800);
  color: var(--signal-yellow);
}

.section-index__link[data-active="true"] .section-index__num { color: var(--signal-yellow); }

/* 17. 筛选 ---------------------------------------------------------------- */
.filters {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

.filter {
  padding: 6px 12px;
  border: var(--line) solid var(--grid-gray);
  background: transparent;
  color: var(--pit-white);
  font-family: var(--font-index);
  font-size: var(--fs-index);
  letter-spacing: 0.06em;
  transition: background-color 0.16s ease, color 0.16s ease, border-color 0.16s ease;
}

.filter:hover { border-color: var(--signal-yellow); color: var(--signal-yellow); }

.filter[aria-pressed="true"] {
  background: var(--signal-yellow);
  border-color: var(--signal-yellow);
  color: var(--asphalt-900);
}

/* 18. 图片容器（页面阶段放置 <img>） ------------------------------------- */
.figure {
  margin: 0;
  border: var(--line) solid var(--grid-gray);
  background: var(--asphalt-800);
  box-shadow: var(--shadow-hard);
}

.figure__media {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background-color: var(--asphalt-800);
  background-image: repeating-linear-gradient(
    135deg,
    rgba(127, 182, 178, 0.1) 0 2px,
    rgba(127, 182, 178, 0) 2px 10px
  );
}

.figure__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.92) contrast(1.06) brightness(0.94);
}

.figure__caption {
  padding: 10px 14px;
  border-top: var(--line) solid var(--grid-gray);
  font-family: var(--font-index);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--mist-cyan);
}

.figure--wide .figure__media { aspect-ratio: 21 / 9; }
.figure--tall .figure__media { aspect-ratio: 3 / 4; }
.figure--offset { transform: translateY(18px); }

/* 19. 显现（由 JS 写入 data-reveal="shown"） ----------------------------- */
[data-reveal] { transition: opacity 0.5s ease, transform 0.5s ease; }

html.js-ready [data-reveal]:not([data-reveal="shown"]) {
  opacity: 0;
  transform: translateY(14px);
}

[data-reveal="shown"] { opacity: 1; transform: none; }

/* 20. 响应式 -------------------------------------------------------------- */
@media (max-width: 1080px) {
  .footer-top { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 980px) {
  .grid--8-4 { grid-template-columns: minmax(0, 1fr); }
  .panel--sticky { position: static; top: auto; }
}

@media (max-width: 900px) {
  :root { --sticky-offset: 120px; }

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

  .nav-toggle { display: inline-flex; }

  .status-hint {
    order: 3;
    flex: 1 1 100%;
    padding-top: 10px;
    border-top: var(--line) solid var(--grid-gray);
    justify-content: flex-start;
  }

  .site-nav { display: none; }
  .site-nav[data-open="true"] { display: block; }

  .site-nav__inner {
    flex-direction: column;
    align-items: stretch;
    gap: 14px;
    padding-block: 14px;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .site-nav__item + .site-nav__item { border-top: var(--line) solid var(--grid-gray); }

  .site-nav__link {
    width: 100%;
    padding: 12px 4px;
    border-color: transparent;
  }

  .site-nav__link[aria-current="page"] { padding-inline: 10px; }

  .site-nav__actions {
    flex-direction: column;
    align-items: stretch;
  }

  .site-nav__actions .btn { width: 100%; }

  .card--offset,
  .figure--offset { transform: none; }
  .card--offset:hover { transform: translateY(-4px); }
}

@media (max-width: 640px) {
  .footer-top { grid-template-columns: minmax(0, 1fr); }
  .grid--3 { grid-template-columns: minmax(0, 1fr); }
  .brand__name { font-size: 18px; }
  .footer-bottom { justify-content: flex-start; }
  .stats { grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); }
}

/* 21. 动效降级 ------------------------------------------------------------ */
@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;
  }

  [data-reveal],
  html.js-ready [data-reveal]:not([data-reveal="shown"]) {
    opacity: 1 !important;
    transform: none !important;
  }

  .card:hover { transform: none; }
  .card--offset { transform: none; }
  .figure--offset { transform: none; }
}