/* =========================================================
   皇冠国际娱乐 · 共享样式 /assets/site.css
   蓝图网格 · 编号导轨 · 编辑部目录页脚
   ========================================================= */

/* ---------- reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body,
h1, h2, h3, h4, h5, h6,
p, figure, blockquote, dl, dd, ol, ul {
  margin: 0;
}

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

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

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

button, input, select, textarea { font: inherit; color: inherit; }

button { background: none; border: 0; }

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

main { display: block; }

/* ---------- 设计变量 ---------- */
:root {
  --ink: #07060A;
  --layer: #100E17;
  --layer-2: #0B0911;
  --steel: #2A2536;
  --gold: #D6A94A;
  --gold-bright: #F3DE9E;
  --royal: #6B3FD4;
  --royal-deep: #2B1550;
  --neon: #2BE3D6;
  --text: #CFCADD;
  --text-dim: #8B84A3;
  --coral: #FF6B6B;

  --rail-w: 72px;
  --shell: 1280px;
  --gap: clamp(1.15rem, 2.4vw, 2.25rem);

  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", Georgia, serif;
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "Roboto Mono", "DIN Alternate", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --shadow-stack: 9px 9px 0 -1px var(--layer-2), 9px 9px 0 0 var(--steel);
}

/* ---------- 基础排版 ---------- */
body {
  min-height: 100vh;
  padding-left: var(--rail-w);
  overflow-x: hidden;
  background-color: var(--ink);
  background-image:
    radial-gradient(120% 70% at 12% -6%, rgba(107, 63, 212, 0.26), transparent 58%),
    radial-gradient(90% 55% at 96% 4%, rgba(43, 227, 214, 0.09), transparent 52%),
    linear-gradient(rgba(42, 37, 54, 0.5) 1px, transparent 1px),
    linear-gradient(90deg, rgba(42, 37, 54, 0.5) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 48px 48px, 48px 48px;
  background-attachment: fixed, fixed, fixed, fixed;
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  font-weight: 700;
  line-height: 1.24;
  color: #F4F1FA;
}

h1 { font-size: clamp(2.1rem, 5.4vw, 4.2rem); letter-spacing: 0.02em; }
h2 { font-size: clamp(1.55rem, 3.2vw, 2.4rem); }
h3 { font-size: clamp(1.2rem, 2.1vw, 1.6rem); }

::selection { background: rgba(107, 63, 212, 0.55); color: #FFF6E0; }

/* ---------- 无障碍 ---------- */
:focus-visible {
  outline: 2px solid var(--neon);
  outline-offset: 2px;
  box-shadow: 0 0 0 5px rgba(43, 227, 214, 0.18);
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -90px;
  z-index: 300;
  padding: 0.7rem 1.15rem;
  background: linear-gradient(120deg, var(--gold), var(--gold-bright));
  color: #16110A;
  font-size: 13px;
  letter-spacing: 0.12em;
  transition: top 0.18s ease;
}

.skip-link:focus { top: 1rem; }

/* =========================================================
   页头
   ========================================================= */
.site-header { position: relative; z-index: 90; }

.topbar {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 72px;
  padding: 0 clamp(1.15rem, 3vw, 2.75rem);
  background: linear-gradient(180deg, rgba(16, 14, 23, 0.94), rgba(7, 6, 10, 0.78));
  border-bottom: 1px solid rgba(214, 169, 74, 0.3);
}

.topbar::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 1px;
  background: linear-gradient(90deg,
    transparent,
    rgba(243, 222, 158, 0.5) 16%,
    rgba(214, 169, 74, 0.9) 50%,
    rgba(243, 222, 158, 0.5) 84%,
    transparent);
}

.topbar__right {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.topbar__cta { flex: 0 0 auto; }

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--gold-bright);
}

.brand__mark {
  display: block;
  width: 32px;
  height: 24px;
  color: var(--gold);
  filter: drop-shadow(0 0 8px rgba(214, 169, 74, 0.35));
}

.brand__mark svg { width: 100%; height: 100%; }

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.05;
}

.brand__name {
  font-family: var(--font-serif);
  font-size: 1.16rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--gold-bright);
}

.brand__sub {
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.34em;
  color: var(--text-dim);
}

.brand--footer .brand__mark { width: 40px; height: 30px; }
.brand--footer .brand__name { font-size: 1.35rem; }

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.55rem;
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--steel);
  color: var(--text);
  font-size: 12px;
  letter-spacing: 0.18em;
  cursor: pointer;
  transition: border-color 0.2s ease, color 0.2s ease;
}

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

.nav-toggle__bars {
  display: inline-flex;
  flex-direction: column;
  gap: 4px;
  width: 18px;
}

.nav-toggle__bars span {
  display: block;
  height: 1px;
  background: currentColor;
  transition: transform 0.22s ease, opacity 0.22s ease;
}

.nav-toggle__bars span:nth-child(2) { width: 70%; }

.site-header[data-open] .nav-toggle__bars span:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.site-header[data-open] .nav-toggle__bars span:nth-child(2) { opacity: 0; }
.site-header[data-open] .nav-toggle__bars span:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }

/* 编号导轨 */
.rail {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  z-index: 80;
  display: flex;
  flex-direction: column;
  width: var(--rail-w);
  background: linear-gradient(180deg, #0B0911 0%, var(--layer) 46%, #0B0911 100%);
  border-right: 1px solid var(--steel);
}

.rail::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 5px;
  background-image: repeating-linear-gradient(90deg, rgba(214, 169, 74, 0.6) 0 1px, transparent 1px 12px);
}

.rail__list {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  width: 100%;
  margin: auto 0;
  padding-block: 1.25rem;
  overflow-y: auto;
}

.rail__item { width: 100%; }

.rail__link {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  width: 100%;
  padding: 0.6rem 0.35rem;
  color: var(--text-dim);
  transition: color 0.2s ease, transform 0.2s ease;
}

.rail__link::before {
  content: "";
  position: absolute;
  left: 9px;
  top: 50%;
  transform: translateY(-50%);
  width: 2px;
  height: 0;
  border-radius: 2px;
  background: var(--neon);
  transition: height 0.24s ease;
}

.rail__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--steel);
  transition: color 0.2s ease;
}

.rail__label {
  writing-mode: vertical-rl;
  font-size: 12px;
  letter-spacing: 0.28em;
  transition: color 0.2s ease;
}

.rail__link:hover { color: var(--gold-bright); transform: translateY(-4px); }
.rail__link:hover .rail__num { color: var(--gold); }

.rail__link[aria-current="page"] { color: var(--neon); }
.rail__link[aria-current="page"] .rail__num { color: var(--neon); }
.rail__link[aria-current="page"] .rail__label { text-shadow: 0 0 12px rgba(43, 227, 214, 0.55); }
.rail__link[aria-current="page"]::before {
  height: 28px;
  box-shadow: 0 0 14px rgba(43, 227, 214, 0.85);
}

.rail__meter {
  position: absolute;
  left: 50%;
  bottom: 0;
  transform: translateX(-50%);
  width: 2px;
  height: 130px;
  background: rgba(42, 37, 54, 0.9);
  overflow: hidden;
}

.rail__meter-fill {
  display: block;
  width: 100%;
  height: calc(var(--p, 0) * 1%);
  background: linear-gradient(180deg, var(--neon), var(--gold));
}

/* =========================================================
   页脚
   ========================================================= */
.site-footer {
  position: relative;
  margin-top: clamp(3.5rem, 8vw, 7rem);
  border-top: 1px solid var(--steel);
  background:
    radial-gradient(110% 70% at 10% 0%, rgba(107, 63, 212, 0.24), transparent 62%),
    linear-gradient(180deg, #0A0813 0%, var(--ink) 72%);
  padding-top: clamp(2.25rem, 4.5vw, 4rem);
}

.footer__head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-bottom: clamp(1.25rem, 2.6vw, 2rem);
  margin-bottom: clamp(1.5rem, 3.4vw, 2.5rem);
  border-bottom: 1px solid var(--steel);
}

.footer__tag {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--text-dim);
}

.footer__grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1.2fr) minmax(0, 0.95fr);
  gap: clamp(1.75rem, 4vw, 3.5rem);
  padding-bottom: clamp(1.75rem, 3.6vw, 3rem);
}

.footer__col { min-width: 0; }

.footer__title {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 1rem;
  font-family: var(--font-sans);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.24em;
  color: var(--gold);
}

.footer__title::after {
  content: "";
  flex: 1 1 auto;
  height: 1px;
  background: linear-gradient(90deg, rgba(214, 169, 74, 0.45), transparent);
}

.footer__list { display: grid; gap: 0.1rem; }

.footer__item { min-width: 0; }

.footer__link {
  display: flex;
  align-items: baseline;
  gap: 0.7rem;
  padding: 0.42rem 0;
  font-size: 14.5px;
  color: var(--text-dim);
  border-bottom: 1px dashed rgba(42, 37, 54, 0.9);
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.footer__link:hover {
  color: var(--gold-bright);
  padding-left: 0.4rem;
}

.footer__link[aria-current="page"] { color: var(--neon); }

.footer__link--inline {
  display: inline;
  padding: 0.15rem 0;
  border-bottom: 1px solid rgba(42, 37, 54, 0.95);
  font-size: 12.5px;
}

.footer__link--inline:hover {
  padding-left: 0;
  color: var(--gold-bright);
  border-color: rgba(214, 169, 74, 0.6);
}

.footer__num {
  flex: 0 0 auto;
  min-width: 1.8em;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--gold);
}

.footer__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.15rem 0.75rem;
  padding: 0.42rem 0;
  font-size: 14.5px;
  color: var(--text-dim);
  border-bottom: 1px dashed rgba(42, 37, 54, 0.9);
}

.footer__label {
  flex: 0 0 auto;
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--gold);
}

.footer__value {
  color: var(--text);
  word-break: break-word;
}

.footer__note {
  margin-top: 0.85rem;
  font-size: 13px;
  line-height: 1.8;
  color: var(--text-dim);
}

.footer__mono {
  font-family: var(--font-mono);
  color: var(--neon);
  letter-spacing: 0.06em;
}

.footer__baseline {
  position: relative;
  height: 14px;
  border-top: 1px solid rgba(214, 169, 74, 0.55);
}

.footer__baseline::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 6px;
  background-image: repeating-linear-gradient(90deg, rgba(214, 169, 74, 0.5) 0 1px, transparent 1px 24px);
}

.footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.7rem 1.5rem;
  padding: 1.25rem 0 1.9rem;
  font-size: 12.5px;
  color: var(--text-dim);
}

.footer__bottom-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1.1rem;
}

/* =========================================================
   通用组件
   ========================================================= */
.container {
  width: 100%;
  max-width: var(--shell);
  margin-inline: auto;
  padding-inline: clamp(1.15rem, 3vw, 3rem);
}

.section {
  position: relative;
  padding-block: clamp(2.75rem, 6.5vw, 5.5rem);
}

.section-head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  gap: 0.9rem 1.25rem;
  padding-bottom: 1rem;
  margin-bottom: clamp(1.5rem, 3vw, 2.5rem);
  border-bottom: 1px solid var(--steel);
}

.section-head__num {
  font-family: var(--font-mono);
  font-size: clamp(1.15rem, 2vw, 1.5rem);
  color: var(--gold);
  letter-spacing: 0.08em;
  line-height: 1;
}

.section-head__title { margin: 0; }

.section-head__note {
  writing-mode: vertical-rl;
  margin-left: auto;
  max-height: 7em;
  font-size: 12px;
  letter-spacing: 0.3em;
  color: var(--text-dim);
}

.vertical-note {
  writing-mode: vertical-rl;
  font-size: 12px;
  letter-spacing: 0.3em;
  color: var(--text-dim);
}

.rule {
  position: relative;
  height: 1px;
  margin-block: clamp(1.75rem, 3.6vw, 3rem);
  background: linear-gradient(90deg, rgba(214, 169, 74, 0.62), rgba(42, 37, 54, 0.28) 62%, transparent);
}

.rule::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 5px;
  background-image: repeating-linear-gradient(90deg, rgba(214, 169, 74, 0.42) 0 1px, transparent 1px 24px);
}

.big-num {
  display: block;
  font-family: var(--font-mono);
  font-size: clamp(2.4rem, 5.6vw, 3.3rem);
  line-height: 1;
  letter-spacing: 0.04em;
  color: transparent;
  -webkit-text-stroke: 1px var(--gold);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.28rem 0.6rem;
  border: 1px solid var(--steel);
  background: rgba(16, 14, 23, 0.72);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.tag--gold { border-color: rgba(214, 169, 74, 0.55); color: var(--gold-bright); }
.tag--royal { border-color: rgba(107, 63, 212, 0.7); color: #B79CFF; }
.tag--neon { border-color: rgba(43, 227, 214, 0.5); color: var(--neon); }
.tag--alert { border-color: rgba(255, 107, 107, 0.55); color: var(--coral); }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.7rem 1.2rem;
  border: 1px solid var(--gold);
  background: transparent;
  color: var(--gold-bright);
  font-size: 14px;
  letter-spacing: 0.1em;
  line-height: 1.2;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

.btn:hover {
  background: rgba(214, 169, 74, 0.14);
  box-shadow: 0 10px 26px -16px rgba(214, 169, 74, 0.9);
  transform: translateY(-2px);
}

.btn--gold {
  background: linear-gradient(120deg, var(--gold), var(--gold-bright));
  border-color: var(--gold-bright);
  color: #171006;
  font-weight: 600;
}

.btn--gold:hover { background: linear-gradient(120deg, var(--gold-bright), #FFF3C8); }

.btn--neon { border-color: var(--neon); color: var(--neon); }
.btn--neon:hover { background: rgba(43, 227, 214, 0.12); }

.btn--ghost { border-color: var(--steel); color: var(--text); }
.btn--ghost:hover { border-color: var(--gold); color: var(--gold-bright); }

.btn--sm { padding: 0.45rem 0.85rem; font-size: 12.5px; }

.panel {
  position: relative;
  padding: clamp(1.15rem, 2.2vw, 1.85rem);
  background: var(--layer);
  border: 1px solid var(--steel);
}

.panel--stacked { box-shadow: var(--shadow-stack); }

.panel__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.6rem 1rem;
  padding-bottom: 0.75rem;
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--steel);
}

.panel__title {
  margin: 0;
  font-size: 1.1rem;
  letter-spacing: 0.02em;
}

.panel__meta {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--text-dim);
}

.panel__body { font-size: 15.5px; color: var(--text); }

.index-list { display: grid; gap: 0.35rem; }

.index-list__item {
  display: flex;
  align-items: baseline;
  gap: 0.9rem;
  padding: 0.7rem 0.85rem;
  background: rgba(16, 14, 23, 0.7);
  border: 1px solid var(--steel);
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.index-list__item:hover {
  border-color: rgba(214, 169, 74, 0.55);
  transform: translateX(4px);
}

.index-list__num {
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--gold);
  letter-spacing: 0.06em;
}

.index-list__text { min-width: 0; font-size: 15px; }

.media { position: relative; }

.media__frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border: 1px solid var(--steel);
  background:
    radial-gradient(80% 80% at 20% 10%, rgba(107, 63, 212, 0.35), transparent 60%),
    linear-gradient(140deg, #0B0911, #1A1030 55%, #0B0911);
}

.media__frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media__frame::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 5px;
  background-image: repeating-linear-gradient(90deg, rgba(214, 169, 74, 0.5) 0 1px, transparent 1px 18px);
}

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

.media__caption {
  margin-top: 0.6rem;
  font-size: 12.5px;
  letter-spacing: 0.06em;
  color: var(--text-dim);
}

.breadcrumb { padding-block: 1.15rem 0; }

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  font-size: 12.5px;
  letter-spacing: 0.08em;
  color: var(--text-dim);
}

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

.breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  margin-right: 0.5rem;
  color: var(--steel);
}

.breadcrumb__link { color: var(--text-dim); transition: color 0.2s ease; }
.breadcrumb__link:hover { color: var(--neon); }
.breadcrumb__item[aria-current="page"] { color: var(--gold-bright); }

.prose {
  max-width: 70ch;
  font-size: 17px;
  line-height: 1.75;
  color: var(--text);
}

.prose > * + * { margin-top: 1.2em; }
.prose h2 { margin-top: 2em; font-size: clamp(1.4rem, 2.6vw, 1.9rem); }
.prose h3 { margin-top: 1.6em; }
.prose ul,
.prose ol { padding-left: 1.3em; }
.prose ul { list-style: none; }
.prose ul li { position: relative; padding-left: 0.2em; }
.prose ul li::before {
  content: "";
  position: absolute;
  left: -1em;
  top: 0.82em;
  width: 0.5em;
  height: 1px;
  background: var(--gold);
}
.prose ol { list-style: decimal; }
.prose ol li::marker { color: var(--gold); font-family: var(--font-mono); }
.prose a { color: var(--neon); border-bottom: 1px solid rgba(43, 227, 214, 0.4); }
.prose a:hover { border-color: var(--neon); }
.prose strong { color: var(--gold-bright); }
.prose blockquote {
  padding-left: 1.1rem;
  border-left: 2px solid var(--royal);
  color: var(--text-dim);
}

.grid {
  display: grid;
  gap: var(--gap);
}

.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.grid--12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }

.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-5 { grid-column: span 5; }
.span-6 { grid-column: span 6; }
.span-7 { grid-column: span 7; }
.span-8 { grid-column: span 8; }
.span-9 { grid-column: span 9; }
.span-12 { grid-column: span 12; }

/* 显现 */
.reveal { opacity: 1; transform: none; }

html.js .reveal {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.24s ease, transform 0.24s ease;
}

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

/* 标签页 */
.tabs { position: relative; }

.tabs__list {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--steel);
  overflow-x: auto;
  scrollbar-width: thin;
}

.tabs__tab {
  flex: 0 0 auto;
  padding: 0.85rem 1.25rem;
  border: 1px solid transparent;
  border-bottom: 0;
  background: transparent;
  color: var(--text-dim);
  font-size: 13px;
  letter-spacing: 0.14em;
  white-space: nowrap;
  cursor: pointer;
  transition: color 0.2s ease, background 0.2s ease;
}

.tabs__tab:hover { color: var(--gold-bright); }

.tabs__tab[aria-selected="true"] {
  color: var(--gold-bright);
  border-color: var(--steel);
  background: linear-gradient(180deg, rgba(107, 63, 212, 0.42), rgba(43, 21, 80, 0.16));
  box-shadow: inset 0 -3px 0 var(--neon);
}

.tabs__panel {
  padding-block: clamp(1.25rem, 2.6vw, 2rem);
  animation: panel-in 0.24s ease both;
}

.tabs__panel[hidden] { display: none; }

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

/* =========================================================
   响应式
   ========================================================= */
@media (max-width: 1100px) {
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer__grid { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
  .footer__col:last-child { grid-column: 1 / -1; }
}

@media (max-width: 900px) {
  body {
    padding-left: 0;
    background-attachment: scroll, scroll, fixed, fixed;
  }

  .site-header {
    position: sticky;
    top: 0;
    z-index: 120;
    background: rgba(7, 6, 10, 0.94);
    -webkit-backdrop-filter: blur(12px);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--steel);
  }

  .topbar {
    min-height: 60px;
    background: transparent;
    border-bottom: 0;
  }

  .topbar::after { display: none; }

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

  .rail {
    position: static;
    width: 100%;
    background: var(--layer-2);
    border-right: 0;
    border-top: 1px solid var(--steel);
  }

  .rail::before {
    top: auto;
    bottom: 0;
    height: 3px;
  }

  .site-header[data-enhanced]:not([data-open]) .rail { display: none; }

  .site-header[data-open] .rail { animation: rail-in 0.22s ease both; }

  .rail__list {
    flex-direction: row;
    gap: 0;
    margin: 0;
    padding-block: 0;
    overflow-x: auto;
    overflow-y: hidden;
    scroll-snap-type: x proximity;
    -webkit-overflow-scrolling: touch;
  }

  .rail__item {
    flex: 0 0 auto;
    width: auto;
    border-right: 1px solid var(--steel);
  }

  .rail__item:last-child { border-right: 0; }

  .rail__link {
    flex-direction: row;
    align-items: center;
    gap: 0.55rem;
    width: auto;
    padding: 0.85rem 1.1rem;
    white-space: nowrap;
    scroll-snap-align: center;
  }

  .rail__link::before {
    left: 0;
    top: auto;
    bottom: 0;
    transform: none;
    width: 0;
    height: 2px;
    transition: width 0.24s ease;
  }

  .rail__link[aria-current="page"]::before { width: 100%; height: 2px; }
  .rail__link:hover { transform: none; }

  .rail__label {
    writing-mode: horizontal-tb;
    font-size: 13px;
    letter-spacing: 0.16em;
  }

  .rail__num { font-size: 11px; }

  .rail__meter {
    position: static;
    transform: none;
    width: 100%;
    height: 2px;
    background: rgba(42, 37, 54, 0.9);
  }

  .rail__meter-fill {
    width: calc(var(--p, 0) * 1%);
    height: 100%;
    background: linear-gradient(90deg, var(--royal), var(--neon), var(--gold));
  }

  .section-head__note { display: none; }

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

  .grid--12 > [class*="span-"] { grid-column: 1 / -1; }

  .footer__grid { grid-template-columns: minmax(0, 1fr); }
  .footer__col:last-child { grid-column: auto; }
}

@media (max-width: 560px) {
  body { font-size: 16px; }
  .brand__sub { display: none; }
  .topbar__cta { padding: 0.55rem 0.8rem; font-size: 13px; }
  .footer__bottom { flex-direction: column; align-items: flex-start; }
}

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

/* ---------- 减少动效 ---------- */
@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 { opacity: 1; transform: none; }
  .rail__link:hover { transform: none; }
  .index-list__item:hover { transform: none; }
  .btn:hover { transform: none; }
}