/* ==========================================================================
   万搏看台 · 共享外壳样式表 /assets/site.css
   刻度尺母题 · 暮色蓝底 · 铜橙点火 · 玻璃层与实色层并置
   ========================================================================== */

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}
html[data-nav-lock] { overflow: hidden; }

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.75;
  background: var(--ink-900);
  color: var(--light-100);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, p, dl, dd, dt, figure, blockquote { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
img, svg, video { display: block; max-width: 100%; }
table { border-collapse: collapse; width: 100%; }
[id] { scroll-margin-top: calc(var(--header-h) + 20px); }

:focus-visible {
  outline: 2px solid var(--copper-300);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ---------- 2. tokens ---------- */
:root {
  --ink-900: #0A1A2F;
  --blue-700: #123055;
  --blue-500: #1B4C86;
  --blue-200: #9FBEE0;
  --copper-500: #C8762A;
  --copper-300: #E7B27C;
  --foam-500: #2FB3A3;
  --seal-700: #B0322A;
  --paper-50: #F5F7FA;
  --text-900: #0E1622;
  --grid-300: #C9D6E6;
  --light-100: #E8EEF6;

  --font-sans: "Source Han Sans SC", "HarmonyOS Sans SC", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui,
    -apple-system, "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular,
    Menlo, Consolas, "Liberation Mono", monospace;

  --header-h: 76px;
  --container-max: 1280px;
  --bleed-max: 1440px;
  --gutter: 24px;

  --radius: 14px;
  --radius-sm: 9px;
  --ease: cubic-bezier(0.2, 0.7, 0.3, 1);
  --dur: 0.2s;

  --line-soft: rgba(159, 190, 224, 0.2);
  --line-mid: rgba(159, 190, 224, 0.32);
  --text-dim: rgba(232, 238, 246, 0.78);
  --glass: rgba(159, 190, 224, 0.08);
}

/* ---------- 3. 排版基础 ---------- */
strong, b { font-weight: 700; color: #fff; }

.lead {
  font-size: 19px;
  line-height: 1.7;
  color: var(--text-dim);
  max-width: 62ch;
}

.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- 4. 布局 ---------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--gutter);
}
.container--bleed { max-width: var(--bleed-max); }

#main-content { padding-top: var(--header-h); }
.overlay-hero {
  margin-top: calc(var(--header-h) * -1);
  padding-top: calc(var(--header-h) + 40px);
}

.section { padding: clamp(48px, 7vw, 88px) 0; }
.section--tight { padding: clamp(32px, 4vw, 52px) 0; }

.section-head { max-width: 72ch; margin-bottom: clamp(24px, 3vw, 40px); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--copper-300);
}
.eyebrow::before {
  content: "";
  display: block;
  width: 22px;
  height: 1px;
  background: currentColor;
}

.section-title {
  font-size: clamp(26px, 3.2vw, 34px);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -0.005em;
  color: #fff;
  margin-top: 10px;
}

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
}
.col-3  { grid-column: span 3; }
.col-4  { grid-column: span 4; }
.col-6  { grid-column: span 6; }
.col-8  { grid-column: span 8; }
.col-12 { grid-column: span 12; }

/* ---------- 5. 表面切换 ---------- */
.surface-paper {
  background: var(--paper-50);
  color: var(--text-900);
}
.surface-paper .section-title { color: var(--text-900); }
.surface-paper .eyebrow { color: var(--blue-500); }
.surface-paper .lead { color: #33465C; }
.surface-paper .card {
  background: #ffffff;
  border-color: var(--grid-300);
  color: var(--text-900);
}

/* ---------- 6. 卡片 / 面板 ---------- */
.card {
  background: rgba(18, 48, 85, 0.55);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  padding: 22px;
}
.card--glass {
  background: var(--glass);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}
.card--solid {
  background: var(--paper-50);
  border-color: var(--grid-300);
  color: var(--text-900);
}

.panel {
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-sm);
  background: rgba(10, 26, 47, 0.35);
  overflow: hidden;
}
.panel + .panel { margin-top: 12px; }
.panel__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 15px 18px;
  font-weight: 600;
  font-size: 16px;
  cursor: pointer;
  list-style: none;
}
.panel__summary::-webkit-details-marker { display: none; }
.panel__summary::after {
  content: "+";
  font-family: var(--font-mono);
  color: var(--copper-300);
  font-size: 18px;
  line-height: 1;
}
.panel[open] .panel__summary::after { content: "−"; }
.panel__body {
  padding: 0 18px 18px;
  font-size: 16px;
  line-height: 1.7;
  color: var(--text-dim);
}
.surface-paper .panel {
  background: #ffffff;
  border-color: var(--grid-300);
}
.surface-paper .panel__summary { color: var(--text-900); }
.surface-paper .panel__body { color: #3A4A5E; }

/* ---------- 7. 按钮 / 标签 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 18px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.02em;
  white-space: nowrap;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}
.btn--copper {
  background: var(--copper-500);
  color: #FFF6EC;
}
.btn--copper:hover {
  background: var(--copper-300);
  color: var(--ink-900);
}
.btn--ghost {
  background: var(--glass);
  border-color: var(--line-mid);
  color: var(--light-100);
}
.btn--ghost:hover {
  border-color: var(--copper-300);
  color: var(--copper-300);
}
.btn--block { width: 100%; }

.tag {
  display: inline-flex;
  align-items: center;
  padding: 3px 9px;
  border: 1px solid currentColor;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
}
.tag--copper { color: var(--copper-300); }
.tag--foam { color: var(--foam-500); }
.tag--seal {
  color: #F2C9C4;
  background: rgba(176, 50, 42, 0.16);
  border-color: rgba(176, 50, 42, 0.7);
}

/* ---------- 8. 数字 / 刻度 ---------- */
.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
}
.num--xl {
  display: inline-block;
  font-size: clamp(48px, 7vw, 96px);
  line-height: 1;
  font-weight: 700;
  color: var(--copper-500);
}
.num--unit {
  font-family: var(--font-mono);
  font-size: 0.42em;
  letter-spacing: 0.06em;
  color: var(--blue-200);
  margin-left: 0.4em;
}
.surface-paper .num--unit { color: var(--blue-500); }

.rule-ticks {
  height: 12px;
  border-bottom: 1px solid var(--line-mid);
  background-image: repeating-linear-gradient(90deg,
    rgba(159, 190, 224, 0.55) 0 1px, transparent 1px 16px);
  background-repeat: repeat-x;
  background-position: left bottom;
  background-size: 16px 8px;
}
.surface-paper .rule-ticks {
  border-bottom-color: var(--grid-300);
  background-image: repeating-linear-gradient(90deg,
    rgba(27, 76, 134, 0.4) 0 1px, transparent 1px 16px);
}

/* ---------- 9. 表格 / 正文 / 面包屑 ---------- */
.data-table { width: 100%; font-size: 15px; }
.data-table th,
.data-table td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--line-soft);
  text-align: left;
  vertical-align: top;
}
.data-table th {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--blue-200);
}
.data-table td { font-variant-numeric: tabular-nums; }
.surface-paper .data-table th,
.surface-paper .data-table td { border-bottom-color: var(--grid-300); }
.surface-paper .data-table th { color: var(--blue-500); }

.prose {
  max-width: 68ch;
  font-size: 17px;
  line-height: 1.75;
}
.prose p + p,
.prose p + ul,
.prose ul + p { margin-top: 1em; }
.prose ul { list-style: none; }
.prose li {
  position: relative;
  padding-left: 20px;
  margin-top: 0.5em;
}
.prose li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 9px;
  height: 1px;
  background: var(--copper-500);
}
.prose h2 {
  font-size: 26px;
  font-weight: 700;
  line-height: 1.3;
  margin: 1.4em 0 0.5em;
  color: #fff;
}
.prose h3 {
  font-size: 20px;
  font-weight: 700;
  margin: 1.2em 0 0.4em;
  color: #fff;
}
.prose a {
  color: var(--copper-300);
  border-bottom: 1px solid currentColor;
}
.surface-paper .prose { color: var(--text-900); }
.surface-paper .prose h2,
.surface-paper .prose h3 { color: var(--text-900); }
.surface-paper .prose a { color: var(--blue-500); }

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--blue-200);
}
.breadcrumb__item { display: inline-flex; align-items: center; gap: 8px; }
.breadcrumb__link { color: var(--blue-200); }
.breadcrumb__link:hover { color: var(--copper-300); }
.breadcrumb__sep { color: var(--line-mid); }
.breadcrumb__current { color: var(--light-100); }
.surface-paper .breadcrumb,
.surface-paper .breadcrumb__link { color: var(--blue-500); }
.surface-paper .breadcrumb__current { color: var(--text-900); }

/* ---------- 10. 图像容器（供页面阶段放置图片） ---------- */
.figure-frame {
  position: relative;
  border: 1px solid var(--line-mid);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--blue-700);
}
.figure-frame::before,
.figure-frame::after {
  content: "";
  position: absolute;
  width: 14px;
  height: 14px;
  border: 1px solid var(--copper-500);
  pointer-events: none;
  z-index: 2;
}
.figure-frame::before { top: 8px; left: 8px; border-right: 0; border-bottom: 0; }
.figure-frame::after { right: 8px; bottom: 8px; border-top: 0; border-left: 0; }

.figure-frame__caption {
  display: block;
  padding: 10px 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--blue-200);
  border-top: 1px solid var(--line-soft);
  background: rgba(10, 26, 47, 0.5);
}

.img-slot {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: linear-gradient(150deg, #123055 0%, #1B4C86 48%, #0A1A2F 100%);
}
.img-slot::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 26%;
  background-image: repeating-linear-gradient(90deg,
    rgba(159, 190, 224, 0.18) 0 1px, transparent 1px 14px);
  opacity: 0.7;
  pointer-events: none;
}
.img-slot > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.img-slot--wide { aspect-ratio: 21 / 9; }
.img-slot--square { aspect-ratio: 1 / 1; }
.img-slot--portrait { aspect-ratio: 3 / 4; }

@supports not (aspect-ratio: 1 / 1) {
  .img-slot { height: 280px; }
  .img-slot--square { height: 340px; }
}

/* ---------- 11. 跳转链接 ---------- */
.skip-link {
  position: fixed;
  top: 0;
  left: 16px;
  z-index: 300;
  padding: 10px 18px;
  border-radius: 0 0 8px 8px;
  background: var(--copper-300);
  color: var(--ink-900);
  font-size: 14px;
  font-weight: 700;
  transform: translateY(-130%);
  transition: transform 0.16s var(--ease);
}
.skip-link:focus { transform: translateY(0); }

/* ---------- 12. 头部 ---------- */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 200;
  color: var(--light-100);
  background: linear-gradient(180deg, rgba(10, 26, 47, 0.72), rgba(10, 26, 47, 0.28));
  -webkit-backdrop-filter: blur(10px) saturate(1.2);
  backdrop-filter: blur(10px) saturate(1.2);
  border-bottom: 1px solid var(--line-soft);
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease),
    box-shadow var(--dur) var(--ease);
}
.site-header[data-scrolled="true"] {
  background: linear-gradient(180deg, var(--blue-500), var(--blue-700));
  border-bottom-color: rgba(200, 118, 42, 0.55);
  box-shadow: 0 12px 30px rgba(6, 16, 30, 0.38);
}

.header-rail {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: rgba(159, 190, 224, 0.16);
  overflow: hidden;
}
.header-rail__fill {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--foam-500), var(--copper-500));
  transition: width 0.08s linear;
}

.header-inner {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 20px;
  height: var(--header-h);
  max-width: var(--bleed-max);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.brand { display: flex; align-items: center; gap: 11px; }
.brand__mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border: 1px solid var(--copper-500);
  border-radius: 7px;
  background: rgba(200, 118, 42, 0.12);
  color: var(--copper-300);
  font-size: 18px;
  font-weight: 700;
  line-height: 1;
}
.brand__text { display: flex; flex-direction: column; line-height: 1.15; }
.brand__name {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: #fff;
}
.brand__sub {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--blue-200);
}

.nav { justify-self: center; min-width: 0; }
.nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}
.nav__link {
  position: relative;
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 9px 10px;
  border-radius: 7px;
  font-size: 14px;
  color: rgba(232, 238, 246, 0.82);
  transition: color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.nav__link::after {
  content: "";
  position: absolute;
  left: 10px;
  right: 10px;
  bottom: 2px;
  height: 2px;
  background: var(--copper-500);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur) var(--ease);
}
.nav__link:hover {
  color: #fff;
  background: var(--glass);
}
.nav__link[aria-current="page"] { color: #fff; }
.nav__link[aria-current="page"]::after { transform: scaleX(1); }

.nav__idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--blue-200);
}
.nav__link[aria-current="page"] .nav__idx { color: var(--copper-300); }
.nav__label { white-space: nowrap; }

.nav__foot { display: none; }
.nav__foot-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--blue-200);
}
.nav__foot-value {
  font-family: var(--font-mono);
  font-size: 20px;
  color: var(--copper-300);
  margin-bottom: 4px;
}
.nav__foot-note {
  font-size: 13px;
  color: var(--text-dim);
  margin-bottom: 16px;
}

.header-side { display: flex; align-items: center; gap: 14px; }
.header-utility {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  line-height: 1.25;
}
.header-utility__label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  color: var(--blue-200);
}
.header-utility__value {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--light-100);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 10px;
  height: 42px;
  padding: 0 14px;
  border: 1px solid var(--line-mid);
  border-radius: 999px;
  color: var(--light-100);
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}
.nav-toggle:hover { border-color: var(--copper-300); color: var(--copper-300); }
.nav-toggle__bars {
  display: flex;
  flex-direction: column;
  gap: 4px;
  width: 18px;
}
.nav-toggle__bar {
  display: block;
  width: 100%;
  height: 2px;
  background: currentColor;
  transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* ---------- 13. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 8vw, 96px);
  padding: 0 0 26px;
  background: linear-gradient(180deg, var(--blue-700), var(--ink-900));
  border-top: 1px solid var(--line-soft);
  color: var(--light-100);
}
.footer-ticks {
  height: 10px;
  margin-bottom: clamp(32px, 4vw, 52px);
  border-bottom: 1px solid rgba(200, 118, 42, 0.45);
  background-image: repeating-linear-gradient(90deg,
    rgba(159, 190, 224, 0.45) 0 1px, transparent 1px 16px);
  background-repeat: repeat-x;
  background-position: left bottom;
  background-size: 16px 7px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.5fr;
  gap: clamp(24px, 3vw, 40px);
}

.footer-brand__name {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: #fff;
}
.footer-brand__tag {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--copper-300);
  margin-top: 6px;
}
.footer-brand__meta {
  margin-top: 14px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-dim);
}

.footer-col__title {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--blue-200);
  margin-bottom: 14px;
}
.footer-list { display: grid; gap: 2px; }
.footer-link {
  display: inline-block;
  padding: 5px 0;
  font-size: 15px;
  color: rgba(232, 238, 246, 0.85);
  transition: color var(--dur) var(--ease);
}
.footer-link:hover { color: var(--copper-300); }
.footer-link[aria-current="page"] { color: var(--copper-300); }

.footer-contact__list { display: grid; gap: 12px; }
.footer-contact__row { display: grid; gap: 2px; }
.footer-contact__term {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--blue-200);
}
.footer-contact__value {
  font-size: 14px;
  line-height: 1.6;
  color: var(--light-100);
  word-break: break-word;
}

.footer-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
  margin-top: clamp(28px, 4vw, 44px);
  padding-top: 20px;
  border-top: 1px solid var(--line-soft);
  font-size: 13px;
  color: var(--text-dim);
}
.footer-note { max-width: 46ch; }
.footer-icp {
  display: inline-flex;
  align-items: center;
  padding: 4px 10px;
  border: 1px solid rgba(176, 50, 42, 0.75);
  border-radius: 4px;
  background: rgba(176, 50, 42, 0.16);
  color: #F2C9C4;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
}
.footer-copy { font-family: var(--font-mono); font-size: 12px; }

/* ---------- 14. 显现动画 ---------- */
.has-js [data-reveal] {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.24s var(--ease), transform 0.24s var(--ease);
}
.has-js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 15. 响应式 ---------- */
@media (max-width: 1180px) {
  .header-utility { display: none; }
}

@media (max-width: 1080px) {
  :root { --header-h: 64px; }

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

  .nav {
    position: fixed;
    top: 0;
    right: 0;
    height: 100vh;
    height: 100dvh;
    width: min(86vw, 360px);
    padding: calc(var(--header-h) + 20px) 22px 28px;
    overflow-y: auto;
    background: linear-gradient(180deg, var(--blue-700), var(--ink-900));
    border-left: 1px solid var(--line-soft);
    transform: translateX(102%);
    visibility: hidden;
    transition: transform 0.22s var(--ease), visibility 0.22s linear;
    justify-self: stretch;
  }
  .nav[data-open="true"] {
    transform: translateX(0);
    visibility: visible;
  }
  .nav[data-open="true"]::before {
    content: "";
    position: fixed;
    inset: 0;
    z-index: -1;
    background: rgba(6, 16, 30, 0.66);
  }

  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }
  .nav__item { border-bottom: 1px solid rgba(159, 190, 224, 0.14); }
  .nav__link {
    display: flex;
    justify-content: flex-start;
    padding: 16px 4px;
    border-radius: 0;
    font-size: 19px;
    color: var(--light-100);
  }
  .nav__link::after { display: none; }
  .nav__link[aria-current="page"] { color: var(--copper-300); }
  .nav__idx { font-size: 12px; }

  .nav__foot {
    display: block;
    margin-top: 26px;
  }
}

@media (max-width: 900px) {
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); gap: 20px; }
  .col-3, .col-4 { grid-column: span 3; }
  .col-6, .col-8, .col-12 { grid-column: span 6; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 28px; }
}

@media (max-width: 600px) {
  :root { --gutter: 18px; }
  body { font-size: 16.5px; }
  .grid-12 { grid-template-columns: minmax(0, 1fr); gap: 18px; }
  .col-3, .col-4, .col-6, .col-8, .col-12 { grid-column: span 1; }
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-meta { flex-direction: column; align-items: flex-start; }
  .card { padding: 18px; }
  .prose { font-size: 16.5px; }
}

/* ---------- 16. 减少动态效果 ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *,
  *::before,
  *::after {
    transition-duration: 0.001ms !important;
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
  }
  .has-js [data-reveal] {
    opacity: 1;
    transform: none;
  }
  .header-rail__fill { transition: none; }
}