/* ==========================================================================
   NG赛场 · 共享样式表 /assets/site.css
   深墨绿底 · 夜蓝分区 · 荧光青柠强调 · 金属银灰线框
   ========================================================================== */

/* ---------- 1. 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, dl, dd, figure, blockquote { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg, video { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; width: 100%; }
hr { border: 0; border-top: 1px solid var(--line); }
main { display: block; }
:target { scroll-margin-top: calc(var(--topbar-h) + 20px); }
#main-content { scroll-margin-top: calc(var(--topbar-h) + 20px); }

/* ---------- 2. tokens ---------- */
:root {
  --ink: #0A1F19;
  --night: #0E1B2C;
  --card: #123128;
  --lime: #C9F73B;
  --lime-dim: #5C7A1F;
  --orange: #FF8B3D;
  --silver: #A9B7BE;
  --mist: #EAF3EE;
  --line: #1E2E3D;
  --amber: #F0C24B;

  --rail-w: 76px;
  --rail-w-open: 236px;
  --topbar-h: 62px;

  --font-display: "Source Han Sans HC", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --font-serif: "Songti SC", "Source Han Serif SC", "Noto Serif SC", Georgia, "Times New Roman", serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Menlo, Consolas, "Liberation Mono", monospace;

  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --dur-fast: 160ms;
  --dur: 200ms;
  --dur-slow: 240ms;

  --radius: 2px;
  --shell-max: 1320px;
  --measure: 42em;
  --shadow-1: 0 8px 20px rgba(0, 0, 0, 0.35);
  --shadow-2: 0 12px 28px rgba(0, 0, 0, 0.45);
}

/* ---------- 3. base ---------- */
html { background: var(--ink); }
body {
  min-height: 100vh;
  padding-top: var(--topbar-h);
  background-color: var(--ink);
  color: var(--mist);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.75;
  letter-spacing: 0.01em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(169, 183, 190, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(169, 183, 190, 0.05) 1px, transparent 1px);
  background-size: 72px 72px;
}
body::after {
  content: "";
  position: fixed;
  left: 0;
  right: 0;
  top: 0;
  height: 320px;
  z-index: -1;
  pointer-events: none;
  background: radial-gradient(120% 100% at 10% 0%, rgba(201, 247, 59, 0.1), rgba(201, 247, 59, 0) 62%);
}
body.nav-open { overflow: hidden; }
@media (min-width: 1024px) {
  body { padding-left: var(--rail-w); }
}

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: 0.02em;
  color: var(--mist);
}
h1 { font-size: clamp(2rem, 5vw, 3.1rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.1rem); }
h3 { font-size: 1.125rem; letter-spacing: 0.05em; }
p { text-wrap: pretty; }
strong, b { font-weight: 700; color: #FFFFFF; }

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

/* ---------- 4. 通用文字与容器 ---------- */
.shell {
  width: 100%;
  max-width: var(--shell-max);
  margin-inline: auto;
  padding-inline: clamp(16px, 4vw, 40px);
}
.eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--silver);
}
.lede { font-size: clamp(1rem, 1.6vw, 1.15rem); line-height: 1.8; color: #D6E2DB; }
.muted { color: var(--silver); }
.accent { color: var(--lime); }
.serif { font-family: var(--font-serif); font-weight: 600; }
.data { font-family: var(--font-mono); letter-spacing: 0.02em; font-variant-numeric: tabular-nums; }
.divider { height: 1px; background: var(--line); border: 0; }

/* ---------- 5. 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  height: 36px;
  padding: 0 14px;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  white-space: nowrap;
  border: 1px solid transparent;
  border-radius: var(--radius);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease),
    border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.btn:active { transform: translateY(1px); }
.btn--primary { background: var(--lime); color: #06140F; }
.btn--primary:hover { background: var(--lime-dim); color: var(--mist); }
.btn--ghost { background: rgba(18, 49, 40, 0.5); color: var(--mist); border-color: var(--line); }
.btn--ghost:hover { border-color: var(--lime); color: var(--lime); }
.btn--outline { background: transparent; color: var(--lime); border-color: var(--lime-dim); }
.btn--outline:hover { background: rgba(201, 247, 59, 0.12); border-color: var(--lime); }
.btn--block { width: 100%; }

/* ---------- 6. 头部外壳 ---------- */
.site-header { position: relative; z-index: 100; }

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 130;
  padding: 10px 16px;
  background: var(--lime);
  color: #06140F;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  border-radius: var(--radius);
  transform: translateY(-200%);
  transition: transform var(--dur) var(--ease);
}
.skip-link:focus,
.skip-link:focus-visible { transform: translateY(0); outline-color: var(--mist); }

/* ---------- 7. 顶栏 ---------- */
.topbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 2;
  height: var(--topbar-h);
  display: flex;
  align-items: center;
  gap: clamp(12px, 2vw, 28px);
  padding-inline: clamp(14px, 2.4vw, 26px);
  background: rgba(14, 27, 44, 0.94);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.topbar__brand {
  display: flex;
  align-items: center;
  gap: 11px;
  flex: 0 0 auto;
  color: var(--mist);
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--lime);
  background: rgba(201, 247, 59, 0.08);
  border: 1px solid var(--lime-dim);
  border-radius: var(--radius);
}
.topbar__names { display: flex; flex-direction: column; line-height: 1.15; }
.topbar__name {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 800;
  letter-spacing: 0.16em;
  color: var(--mist);
}
.topbar__tagline {
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--silver);
}
.search-hint {
  display: flex;
  align-items: center;
  gap: 9px;
  flex: 0 1 360px;
  min-width: 0;
  height: 34px;
  padding: 0 12px;
  color: var(--silver);
  font-size: 13px;
  background: rgba(10, 31, 25, 0.55);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}
.search-hint:hover { border-color: var(--lime-dim); color: var(--mist); }
.search-hint__icon {
  position: relative;
  width: 11px;
  height: 11px;
  flex: 0 0 auto;
  border: 1px solid currentColor;
  border-radius: 50%;
}
.search-hint__icon::after {
  content: "";
  position: absolute;
  right: -4px;
  bottom: -3px;
  width: 6px;
  height: 1px;
  background: currentColor;
  transform: rotate(45deg);
}
.search-hint__text {
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
}
.topbar__current {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  white-space: nowrap;
}
.topbar__current-key { color: var(--silver); opacity: 0.7; }
.topbar__current-val { color: var(--lime); }
.topbar__actions { display: flex; align-items: center; gap: 8px; flex: 0 0 auto; }

/* ---------- 8. 移动端开关与遮罩 ---------- */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  margin-left: auto;
  height: 36px;
  padding: 0 12px;
  color: var(--mist);
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  transition: color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.nav-toggle:hover { border-color: var(--lime-dim); }
.nav-toggle__bars { display: inline-flex; flex-direction: column; gap: 4px; width: 16px; }
.nav-toggle__bars span {
  display: block;
  height: 1.5px;
  width: 100%;
  background: currentColor;
  transition: transform var(--dur) var(--ease), opacity var(--dur-fast) var(--ease);
}
.nav-toggle[aria-expanded="true"] { color: var(--lime); border-color: var(--lime-dim); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

.nav-scrim {
  position: fixed;
  inset: 0;
  z-index: 3;
  background: rgba(4, 10, 8, 0.72);
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--dur) var(--ease), visibility var(--dur) linear;
}
.nav-scrim[data-open] { opacity: 1; visibility: visible; }

/* ---------- 9. 桌面轨道导航 ---------- */
.rail {
  position: fixed;
  top: var(--topbar-h);
  left: 0;
  bottom: 0;
  z-index: 1;
  width: var(--rail-w);
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 16px 10px 20px;
  overflow: hidden;
  background: linear-gradient(180deg, var(--night) 0%, var(--ink) 78%);
  border-right: 1px solid var(--line);
  transition: width var(--dur-slow) var(--ease), box-shadow var(--dur-slow) var(--ease);
}
.rail:hover,
.rail:focus-within {
  width: var(--rail-w-open);
  box-shadow: 10px 0 32px rgba(0, 0, 0, 0.5);
}
.rail__brand {
  display: flex;
  align-items: center;
  gap: 11px;
  height: 44px;
  padding: 0 6px 12px;
  color: var(--mist);
  border-bottom: 1px solid var(--line);
}
.rail__brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
  opacity: 0;
  transform: translateX(-6px);
  transition: opacity var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}
.rail:hover .rail__brand-text,
.rail:focus-within .rail__brand-text { opacity: 1; transform: none; }
.rail__brand-name {
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.16em;
  white-space: nowrap;
}
.rail__brand-sub {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.14em;
  color: var(--silver);
  white-space: nowrap;
}

.site-nav { display: flex; flex-direction: column; gap: 6px; min-height: 0; }
.site-nav__eyebrow { display: none; }
.site-nav__list { display: flex; flex-direction: column; gap: 2px; }
.site-nav__item { list-style: none; }
.site-nav__link {
  position: relative;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 8px;
  color: var(--silver);
  font-size: 13px;
  border-left: 2px solid transparent;
  border-radius: var(--radius);
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}
.site-nav__index {
  flex: 0 0 auto;
  width: 22px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  opacity: 0.6;
}
.site-nav__label {
  white-space: nowrap;
  opacity: 0;
  transform: translateX(-6px);
  transition: opacity var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease);
}
.rail:hover .site-nav__label,
.rail:focus-within .site-nav__label { opacity: 1; transform: none; }
.site-nav__link:hover { background: var(--card); color: var(--mist); }
.site-nav__link[aria-current="page"] {
  color: var(--lime);
  background: rgba(201, 247, 59, 0.07);
  border-left-color: var(--lime);
}
.site-nav__link[aria-current="page"] .site-nav__index { opacity: 1; color: var(--lime); }
.site-nav__foot { display: none; }
.site-nav__hint {
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.9;
  letter-spacing: 0.06em;
  color: var(--silver);
}

/* ---------- 10. 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: clamp(56px, 8vw, 96px);
  background: var(--night);
  border-top: 1px solid var(--line);
  color: var(--mist);
}
.footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 1.6fr) minmax(0, 1.1fr);
  gap: clamp(28px, 4vw, 48px);
  padding-block: clamp(40px, 6vw, 64px);
}
.footer-brand__mark {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 800;
  letter-spacing: 0.22em;
  color: var(--mist);
  padding-left: 14px;
  border-left: 3px solid var(--lime);
  line-height: 1.1;
}
.footer-brand__line {
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--lime);
}
.footer-brand__summary {
  margin-top: 14px;
  max-width: 34em;
  font-size: 14px;
  line-height: 1.8;
  color: var(--silver);
}
.footer-brand__cta { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 20px; }

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}
.footer-col__title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--mist);
  padding-bottom: 10px;
  margin-bottom: 14px;
  border-bottom: 1px solid var(--line);
}
.footer-col__list { display: flex; flex-direction: column; gap: 10px; }
.footer-link {
  display: inline-block;
  font-size: 14px;
  color: var(--silver);
  transition: color var(--dur) var(--ease), transform var(--dur) var(--ease);
}
.footer-link:hover { color: var(--lime); transform: translateX(3px); }

.footer-contact { display: flex; flex-direction: column; }
.footer-contact__line {
  display: flex;
  gap: 10px;
  font-size: 13px;
  line-height: 1.8;
  padding-bottom: 8px;
}
.footer-contact__key {
  flex: 0 0 60px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--silver);
  padding-top: 2px;
}
.footer-contact__val { font-family: var(--font-mono); color: var(--mist); word-break: break-word; }
.footer-contact__note {
  margin-top: 10px;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: 12px;
  line-height: 1.8;
  color: var(--silver);
}

.footer-base { border-top: 1px solid var(--line); background: rgba(10, 31, 25, 0.55); }
.footer-base__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 24px;
  padding-block: 18px;
}
.footer-base__legal,
.footer-base__copy {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  color: var(--silver);
}
.footer-base__copy { margin-left: auto; }

.to-top {
  position: fixed;
  right: clamp(14px, 2.4vw, 26px);
  bottom: clamp(14px, 2.4vw, 26px);
  z-index: 90;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 14px;
  color: var(--silver);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  background: rgba(14, 27, 44, 0.9);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease),
    visibility var(--dur-slow) linear, color var(--dur) var(--ease), border-color var(--dur) var(--ease);
}
.to-top[data-visible] { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { color: var(--lime); border-color: var(--lime-dim); }
.to-top__glyph { color: var(--lime); font-size: 12px; }

/* ---------- 11. 滚动进度 ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  z-index: 120;
  pointer-events: none;
  transform: scaleX(0);
  transform-origin: left center;
  background: linear-gradient(90deg, var(--lime), var(--orange));
}

/* ---------- 12. 栅格与卡片 ---------- */
.grid { display: grid; gap: clamp(16px, 2.4vw, 28px); }
.grid--2 { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.grid--3 { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
.grid--split { grid-template-columns: minmax(0, 7fr) minmax(0, 4fr); }
@media (max-width: 900px) {
  .grid--split { grid-template-columns: minmax(0, 1fr); }
}

.card {
  position: relative;
  padding: clamp(18px, 2.2vw, 24px);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-1);
  transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}
.card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-2);
  border-color: #27384A;
}
.card__title {
  font-family: var(--font-display);
  font-size: 1.0625rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  color: var(--mist);
}
.card__meta {
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--silver);
}
.card__foot {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  color: var(--silver);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--silver);
  background: rgba(18, 49, 40, 0.6);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
.tag--lime { color: var(--lime); border-color: var(--lime-dim); background: rgba(201, 247, 59, 0.08); }
.tag--orange { color: var(--orange); border-color: rgba(255, 139, 61, 0.4); background: rgba(255, 139, 61, 0.08); }
.tag--amber { color: var(--amber); border-color: rgba(240, 194, 75, 0.35); background: rgba(240, 194, 75, 0.08); }

/* ---------- 13. 章节标题与显现 ---------- */
.section-head { position: relative; padding-left: 20px; }
.section-head__bar {
  position: absolute;
  left: 0;
  top: 0.2em;
  width: 1px;
  height: 2.1em;
  overflow: hidden;
  background: var(--line);
}
.section-head__bar::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--lime);
  transform: scaleY(0);
  transform-origin: top center;
  transition: transform var(--dur-slow) var(--ease);
}
.section-head.is-visible .section-head__bar::after { transform: scaleY(1); }
html:not(.js-on) .section-head__bar::after { transform: scaleY(1); }
.section-head__kicker {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--silver);
}
.section-head__title { margin-top: 6px; }

[data-reveal] { transition: opacity var(--dur-slow) var(--ease), transform var(--dur-slow) var(--ease); }
.js-on [data-reveal] { opacity: 0; transform: translateY(14px); }
.js-on [data-reveal].is-visible { opacity: 1; transform: none; }

/* ---------- 14. 正文容器与面包屑 ---------- */
.prose { max-width: var(--measure); font-size: 17px; line-height: 1.8; color: #DCE8E1; }
.prose > * + * { margin-top: 1.1em; }
.prose h2 { margin-top: 2em; font-size: clamp(1.25rem, 2.2vw, 1.6rem); color: var(--mist); }
.prose h3 { margin-top: 1.6em; font-size: 1.0625rem; letter-spacing: 0.06em; color: var(--mist); }
.prose ul > li { position: relative; padding-left: 1.1em; }
.prose ul > li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.85em;
  width: 9px;
  height: 1px;
  background: var(--lime-dim);
}
.prose ol { list-style: decimal; padding-left: 1.5em; }
.prose ol > li::marker { color: var(--lime); font-family: var(--font-mono); font-size: 0.9em; }
.prose blockquote {
  padding: 4px 0 4px 18px;
  border-left: 1px solid var(--lime-dim);
  font-family: var(--font-serif);
  font-size: 1.08em;
  color: #E4EFE9;
}
.prose a {
  color: var(--lime);
  border-bottom: 1px solid rgba(201, 247, 59, 0.35);
  transition: border-color var(--dur) var(--ease);
}
.prose a:hover { border-bottom-color: var(--lime); }

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--silver);
}
.breadcrumb a { color: var(--silver); transition: color var(--dur-fast) var(--ease); }
.breadcrumb a:hover { color: var(--lime); }
.breadcrumb__sep { color: rgba(169, 183, 190, 0.45); }

/* ---------- 15. 图像占位容器 ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  background: linear-gradient(140deg, var(--card), var(--night) 72%);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}
.media img { width: 100%; height: 100%; object-fit: cover; }
.media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, rgba(10, 31, 25, 0) 45%, rgba(10, 31, 25, 0.6) 100%);
}
.media--16x9 { aspect-ratio: 16 / 9; }
.media--4x3 { aspect-ratio: 4 / 3; }
.media--1x1 { aspect-ratio: 1 / 1; }
.media--3x4 { aspect-ratio: 3 / 4; }
.media__caption {
  position: absolute;
  left: 12px;
  right: 12px;
  bottom: 10px;
  z-index: 1;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--silver);
}

/* ---------- 16. 时间轴基元 ---------- */
.timeline { position: relative; padding-left: 26px; }
.timeline::before {
  content: "";
  position: absolute;
  left: 5px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: var(--line);
}
.timeline__item { position: relative; padding-bottom: 22px; }
.timeline__item::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 0.6em;
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--ink);
  border: 1px solid var(--silver);
  transition: background var(--dur) var(--ease), border-color var(--dur) var(--ease),
    box-shadow var(--dur) var(--ease);
}
.timeline__item.is-active::before {
  background: var(--lime);
  border-color: var(--lime);
  box-shadow: 0 0 0 4px rgba(201, 247, 59, 0.14);
}
.timeline__time {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--lime);
}
.timeline__title {
  margin-top: 4px;
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  color: var(--mist);
}

/* ---------- 17. 响应式 ---------- */
@media (max-width: 1180px) {
  .topbar__actions .btn--ghost { display: none; }
}
@media (max-width: 1023.98px) {
  .search-hint,
  .topbar__current,
  .topbar__actions { display: none; }
  .nav-toggle { display: inline-flex; }

  .rail { display: contents; }
  .rail__brand { display: none; }

  .site-nav {
    position: fixed;
    top: 0;
    left: 0;
    z-index: 4;
    width: min(86vw, 340px);
    height: 100dvh;
    display: flex;
    flex-direction: column;
    gap: 16px;
    padding: 22px 20px 26px;
    overflow-y: auto;
    background: linear-gradient(180deg, var(--night) 0%, var(--ink) 100%);
    border-right: 1px solid var(--line);
    box-shadow: 28px 0 60px rgba(0, 0, 0, 0.55);
    transform: translateX(-102%);
    transition: transform var(--dur-slow) var(--ease);
  }
  .site-nav[data-open] { transform: none; }
  .site-nav__eyebrow {
    display: block;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--lime);
    padding-bottom: 14px;
    border-bottom: 1px solid var(--line);
  }
  .site-nav__list { gap: 4px; }
  .site-nav__link { padding: 12px 10px; font-size: 15px; }
  .site-nav__label { opacity: 1; transform: none; }
  .site-nav__foot {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: auto;
    padding-top: 18px;
    border-top: 1px solid var(--line);
  }
}
@media (max-width: 900px) {
  .footer-grid { grid-template-columns: minmax(0, 1fr); }
  .footer-cols { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
  .topbar__tagline { display: none; }
  .footer-cols { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 22px; }
  .footer-base__copy { margin-left: 0; }
  .to-top { padding: 8px 11px; letter-spacing: 0.12em; }
}

/* ---------- 18. 减少动态效果 ---------- */
@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;
    transition-delay: 0ms !important;
  }
  .js-on [data-reveal] { opacity: 1 !important; transform: none !important; }
  .section-head__bar::after { transform: scaleY(1) !important; }
  .to-top { transform: none; }
}