/* =========================================================
   乐鱼赛场 · 共享样式表  /assets/site.css
   顺序：重置 → 变量 → 排版 → 布局 → 刊头 → 页脚 → 组件 → 动效 → 响应式
   ========================================================= */

/* ---------- 1. 重置 ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body, h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, dl, dd { margin: 0; }
ul, ol { padding: 0; list-style: none; }
a { color: inherit; text-decoration: none; }
button, input, select, textarea { font: inherit; color: inherit; }
button { background: none; border: 0; cursor: pointer; }
img, svg, video { display: block; max-width: 100%; height: auto; }
table { width: 100%; border-collapse: collapse; }
[hidden] { display: none !important; }

/* ---------- 2. 变量 ---------- */
:root {
  --bg: #061B2E;
  --bg-deep: #04121F;
  --card: #0A2A44;
  --cyan: #3DDCDF;
  --cyan-soft: #9BF2F2;
  --orange: #FF8A3D;
  --orange-soft: #FFC496;
  --paper: #F4F7F8;
  --ink: #12212E;
  --line: #6E8899;
  --white: #EAFDFD;

  --wrap: 1240px;
  --gutter: clamp(20px, 4.6vw, 56px);
  --radius: 2px;
  --radius-lg: 3px;

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

  --ease: cubic-bezier(.22, .61, .36, 1);
  --dur: 320ms;

  --hair: rgba(110, 136, 153, .3);
  --hair-cyan: rgba(61, 220, 223, .45);
}

/* ---------- 3. 基础排版 ---------- */
body {
  min-height: 100vh;
  background-color: var(--bg);
  background-image:
    radial-gradient(1200px 620px at 12% -12%, rgba(61, 220, 223, .14), transparent 62%),
    radial-gradient(900px 520px at 96% 4%, rgba(255, 138, 61, .1), transparent 64%);
  background-repeat: no-repeat;
  color: var(--white);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  letter-spacing: .012em;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
@media (min-width: 768px) { body { font-size: 17px; } }
@media (min-width: 1280px) { body { font-size: 18px; } }

h1, h2, h3, h4 { font-weight: 900; line-height: 1.18; letter-spacing: .015em; }
p { max-width: 68ch; }

:focus-visible { outline: 2px solid var(--cyan); outline-offset: 3px; border-radius: var(--radius); }
:focus:not(:focus-visible) { outline: none; }

::selection { background: var(--cyan); color: var(--ink); }

/* ---------- 4. 布局骨架 ---------- */
.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

#main-content {
  display: block;
  padding-block: clamp(24px, 3.6vw, 52px);
}

.section { padding-block: clamp(36px, 5.4vw, 78px); }

.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 26px;
  margin-bottom: clamp(22px, 3vw, 38px);
}
.section__title { font-size: clamp(26px, 3.4vw, 44px); }
.section__note { font-size: 14.5px; color: var(--cyan-soft); max-width: 38ch; }

.eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--cyan);
}

.rule {
  height: 1px;
  border: 0;
  margin-block: clamp(22px, 3.4vw, 46px);
  background: linear-gradient(90deg, var(--cyan), rgba(61, 220, 223, 0));
}

.display {
  font-size: clamp(36px, 6.6vw, 96px);
  line-height: 1.04;
  font-weight: 900;
  letter-spacing: .02em;
}
.display--tight { font-size: clamp(32px, 5vw, 64px); }

.grid { display: grid; gap: clamp(16px, 2.4vw, 28px); }
.grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid--split { grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); }
.grid--aside { grid-template-columns: minmax(220px, 3fr) minmax(0, 9fr); }

.chapter {
  display: grid;
  grid-template-columns: minmax(58px, auto) minmax(0, 1fr);
  gap: clamp(16px, 3vw, 44px);
  align-items: start;
}
.chapter__num {
  font-family: var(--font-mono);
  font-size: clamp(32px, 5.4vw, 64px);
  font-weight: 700;
  line-height: .9;
  letter-spacing: .01em;
  color: var(--cyan);
  opacity: .55;
  font-variant-numeric: tabular-nums;
}
.chapter__body { max-width: 62ch; }

.band { position: relative; }
.band--paper { background: var(--paper); color: var(--ink); }
.band--card { background: var(--card); }
.band--glow {
  background-image:
    radial-gradient(700px 340px at 8% 0%, rgba(61, 220, 223, .16), transparent 68%),
    radial-gradient(620px 320px at 100% 100%, rgba(255, 138, 61, .12), transparent 70%);
  background-repeat: no-repeat;
}

/* ---------- 5. 刊头 ---------- */
.skip-link {
  position: absolute;
  left: 16px;
  top: -70px;
  z-index: 120;
  padding: 10px 18px;
  background: var(--cyan);
  color: var(--ink);
  font-size: 14px;
  font-weight: 700;
  border-radius: var(--radius);
  transition: top var(--dur) var(--ease);
}
.skip-link:focus { top: 14px; }

.masthead {
  position: sticky;
  top: 0;
  z-index: 80;
  background: rgba(6, 27, 46, .94);
  border-bottom: 1px solid var(--hair);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.masthead__inner {
  display: grid;
  grid-template-columns: minmax(160px, 1fr) auto minmax(160px, 1fr);
  align-items: center;
  gap: clamp(14px, 2.6vw, 36px);
  padding-block: clamp(12px, 1.8vw, 20px);
}

.brandmark { display: flex; flex-direction: column; gap: 3px; line-height: 1.06; }
.brandmark__zh {
  font-size: clamp(20px, 2.1vw, 26px);
  font-weight: 900;
  letter-spacing: .08em;
  color: var(--white);
}
.brandmark__en {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .3em;
  color: var(--cyan);
}

.nav { justify-self: center; }
.nav__list { display: flex; align-items: center; gap: clamp(4px, 1.4vw, 18px); }
.nav__item { display: block; }
.nav__link {
  position: relative;
  display: inline-block;
  padding: 8px 10px;
  font-size: 15px;
  font-weight: 500;
  letter-spacing: .08em;
  color: var(--cyan-soft);
  transition: color var(--dur) var(--ease);
}
.nav__link::after {
  content: "";
  position: absolute;
  left: 10px;
  right: 10px;
  bottom: 1px;
  height: 1px;
  background: var(--cyan);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--dur) var(--ease), background var(--dur) var(--ease);
}
.nav__link:hover { color: var(--white); }
.nav__link:hover::after { transform: scaleX(1); }
.nav__link[aria-current="page"] { color: var(--white); font-weight: 700; }
.nav__link[aria-current="page"]::after { transform: scaleX(1); background: var(--orange); }

.masthead__utility {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 10px;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 10px 13px;
  border: 1px solid var(--hair-cyan);
  border-radius: var(--radius);
  color: var(--cyan);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}
.nav-toggle:hover { border-color: var(--cyan); color: var(--white); }
.nav-toggle__bars { display: grid; gap: 4px; width: 18px; }
.nav-toggle__bars span {
  display: block;
  height: 2px;
  background: currentColor;
  transition: transform var(--dur) var(--ease);
}
.nav-toggle__text {
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .18em;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:first-child { transform: translateY(3px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:last-child { transform: translateY(-3px) rotate(-45deg); }

.statusbar {
  border-top: 1px solid rgba(110, 136, 153, .2);
  background: linear-gradient(90deg, rgba(10, 42, 68, .92), rgba(6, 27, 46, .35));
}
.statusbar__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 14px;
  padding-block: 8px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .14em;
  color: var(--cyan-soft);
}
.statusbar__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--orange);
  box-shadow: 0 0 0 3px rgba(255, 138, 61, .18);
  flex: none;
}
.statusbar__label { color: var(--white); }
.statusbar__note { color: var(--line); }
.statusbar__code { margin-left: auto; color: var(--line); }

.scroll-meter {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  overflow: hidden;
  pointer-events: none;
}
.scroll-meter__bar {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--cyan), var(--orange));
  transition: width 110ms linear;
}

/* ---------- 6. 页脚 ---------- */
.site-foot {
  background: var(--bg-deep);
  border-top: 1px solid var(--hair-cyan);
  color: var(--cyan-soft);
}

.foot-index {
  display: grid;
  grid-template-columns: 1.4fr .9fr 1.35fr .9fr;
  gap: clamp(24px, 3.6vw, 54px);
  padding-block: clamp(40px, 5.6vw, 74px) clamp(22px, 3vw, 40px);
}
.foot-col { min-width: 0; }
.foot-col--brand { max-width: 34ch; }

.foot-brand {
  font-size: clamp(20px, 2vw, 24px);
  font-weight: 900;
  letter-spacing: .08em;
  color: var(--white);
}
.foot-desc { margin-top: 12px; font-size: 14.5px; line-height: 1.85; color: var(--cyan-soft); }
.foot-annot { margin-top: 14px; }

.foot-col__title {
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  color: var(--cyan);
}

.foot-list { display: grid; gap: 10px; font-size: 15px; }
.foot-link {
  color: var(--cyan-soft);
  transition: color var(--dur) var(--ease);
}
.foot-link:hover { color: var(--white); }
.foot-link[aria-current="page"] { color: var(--orange); }

.foot-contact { display: grid; gap: 16px; font-size: 14.5px; line-height: 1.7; }
.foot-contact__label {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--line);
}
.foot-contact__value { display: block; margin-top: 3px; color: var(--white); word-break: break-word; }

.copy-btn {
  display: inline-flex;
  align-items: center;
  margin-top: 8px;
  padding: 6px 12px;
  border: 1px solid var(--hair-cyan);
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--cyan);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.copy-btn:hover { border-color: var(--cyan); background: rgba(61, 220, 223, .1); }
.copy-btn[data-copied] { border-color: var(--orange); color: var(--orange); }

.foot-icp {
  margin-top: 18px;
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--line);
}

.foot-bottom { border-top: 1px solid rgba(110, 136, 153, .22); }
.foot-bottom__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  padding-block: 18px;
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--line);
}
.foot-copy { color: var(--line); }
.foot-note { color: rgba(110, 136, 153, .85); max-width: 46ch; }

.to-top {
  position: fixed;
  right: clamp(16px, 2.6vw, 32px);
  bottom: clamp(16px, 2.6vw, 32px);
  z-index: 90;
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border: 1px solid var(--hair-cyan);
  border-radius: var(--radius);
  background: rgba(6, 27, 46, .92);
  color: var(--cyan);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease),
              visibility var(--dur) var(--ease), border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}
.to-top[data-visible] { opacity: 1; visibility: visible; transform: none; }
.to-top:hover { border-color: var(--orange); color: var(--orange); }
.to-top__arrow { font-size: 17px; line-height: 1; }

/* ---------- 7. 通用组件 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 20px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .1em;
  transition: transform var(--dur) var(--ease), background var(--dur) var(--ease),
              border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}
.btn--primary { background: var(--orange); color: var(--ink); }
.btn--primary:hover { background: var(--orange-soft); transform: translateY(-2px); }
.btn--ghost { border-color: var(--hair-cyan); color: var(--cyan); }
.btn--ghost:hover { border-color: var(--cyan); background: rgba(61, 220, 223, .1); transform: translateY(-2px); }
.btn--quiet { padding-inline: 4px; color: var(--cyan-soft); }
.btn--quiet:hover { color: var(--white); }

.tag {
  display: inline-block;
  padding: 4px 10px;
  border: 1px solid var(--hair-cyan);
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
  color: var(--cyan);
}
.tag--orange { border-color: rgba(255, 138, 61, .6); color: var(--orange); }
.tag--paper { border-color: rgba(18, 33, 46, .28); color: var(--ink); }

.card {
  position: relative;
  padding: clamp(18px, 2.2vw, 28px);
  background: var(--card);
  border: 1px solid var(--hair);
  border-radius: var(--radius-lg);
  transition: transform var(--dur) var(--ease), border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease);
}
.card:hover {
  transform: translateY(-4px);
  border-color: rgba(61, 220, 223, .68);
  box-shadow: 0 20px 40px -28px rgba(61, 220, 223, .55);
}
.card__tag {
  display: block;
  margin-bottom: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--orange);
}
.card__title { font-size: clamp(18px, 1.6vw, 22px); font-weight: 800; line-height: 1.35; }
.card__text { margin-top: 10px; font-size: 15px; color: var(--cyan-soft); }
.card__meta {
  margin-top: 14px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: .12em;
  color: var(--line);
}

.paper {
  position: relative;
  padding: clamp(22px, 3vw, 44px);
  background: var(--paper);
  color: var(--ink);
  border-radius: var(--radius-lg);
}
.paper--stack {
  box-shadow: 6px 6px 0 -1px rgba(61, 220, 223, .26), 12px 12px 0 -2px rgba(255, 196, 150, .2);
}
.paper__edge {
  position: absolute;
  inset: 0;
  border: 1px solid rgba(18, 33, 46, .1);
  border-radius: var(--radius-lg);
  pointer-events: none;
}
.paper--stamp::after {
  content: attr(data-stamp);
  position: absolute;
  top: 0;
  right: 0;
  padding: 6px 12px;
  background: var(--orange);
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .16em;
}

.mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; letter-spacing: .06em; }

.data-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  letter-spacing: -.01em;
  color: var(--white);
}
.data-num--cyan { color: var(--cyan); }
.data-num--orange { color: var(--orange); }

.annot {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .16em;
  color: var(--orange-soft);
}
.annot--vertical { writing-mode: vertical-rl; text-orientation: mixed; }

.crumbs { margin-bottom: clamp(20px, 3vw, 36px); }
.crumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .14em;
  color: var(--line);
}
.crumbs__item { display: inline-flex; align-items: center; gap: 8px; }
.crumbs__item::after { content: "/"; color: rgba(110, 136, 153, .55); }
.crumbs__item:last-child::after { display: none; }
.crumbs__link { color: var(--cyan-soft); transition: color var(--dur) var(--ease); }
.crumbs__link:hover { color: var(--cyan); }
.crumbs__current { color: var(--white); }

.prose { max-width: 68ch; font-size: 16.5px; line-height: 1.85; }
.prose h2 { margin-top: 1.9em; font-size: clamp(22px, 2.4vw, 30px); }
.prose h3 { margin-top: 1.6em; font-size: 19px; font-weight: 700; }
.prose p { margin-top: 1em; }
.prose ul { display: grid; gap: .6em; margin-top: 1em; padding-left: 1.25em; list-style: disc; }
.prose li::marker { color: var(--cyan); }
.prose strong { color: var(--white); }
.prose a { color: var(--cyan); border-bottom: 1px solid var(--hair-cyan); }
.prose__lead { font-size: clamp(18px, 1.9vw, 22px); line-height: 1.72; color: var(--cyan-soft); }
.band--paper .prose { color: var(--ink); }
.band--paper .prose a { color: #0d6e72; border-bottom-color: rgba(13, 110, 114, .4); }
.band--paper .prose__lead { color: #35505f; }
.band--paper .prose strong { color: var(--ink); }

.media {
  position: relative;
  width: 100%;
  overflow: hidden;
  border: 1px solid var(--hair);
  border-radius: var(--radius-lg);
  background-image: linear-gradient(140deg, #0A2A44 0%, #061B2E 58%, #123A5A 100%);
}
.media__frame { position: relative; width: 100%; height: 100%; }
.media__img { width: 100%; height: 100%; object-fit: cover; }
.media__cap {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 12px 16px;
  background: linear-gradient(0deg, rgba(6, 27, 46, .94), rgba(6, 27, 46, 0));
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .14em;
  color: var(--cyan-soft);
}
.media--ratio-16-9 { aspect-ratio: 16 / 9; }
.media--ratio-4-3 { aspect-ratio: 4 / 3; }
.media--ratio-1-1 { aspect-ratio: 1 / 1; }
.media--tall { aspect-ratio: 3 / 4; }
.media--wide { aspect-ratio: 21 / 9; }
.media--placeholder {
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: .18em;
  color: rgba(155, 242, 242, .55);
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: clamp(20px, 3vw, 34px);
}
.filter-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 18px;
  border: 1px solid rgba(110, 136, 153, .45);
  border-radius: var(--radius);
  font-size: 14px;
  letter-spacing: .08em;
  color: var(--cyan-soft);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease), background var(--dur) var(--ease);
}
.filter-chip:hover { border-color: var(--cyan); color: var(--white); }
.filter-chip[aria-pressed="true"] {
  border-color: var(--orange);
  background: rgba(255, 138, 61, .12);
  color: var(--white);
}
.filter-chip__count { font-family: var(--font-mono); font-size: 11px; color: var(--line); }
.filter-chip[aria-pressed="true"] .filter-chip__count { color: var(--orange); }

[data-filter-item] { transition: opacity var(--dur) var(--ease); }
[data-filter-item].is-filtered-out { display: none; }

.stat-list {
  display: grid;
  gap: 1px;
  border: 1px solid var(--hair);
  background: var(--hair);
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.stat-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 8px 18px;
  align-items: center;
  padding: 14px 18px;
  background: var(--bg);
  font-size: 15px;
}
.stat-row__label { color: var(--cyan-soft); }

.fold {
  background: var(--card);
  border: 1px solid var(--hair);
  border-radius: var(--radius-lg);
}
.fold + .fold { margin-top: 12px; }
.fold__head {
  display: flex;
  align-items: center;
  gap: 16px;
  width: 100%;
  padding: 18px 20px;
  text-align: left;
  font-size: 17px;
  font-weight: 700;
  color: var(--white);
}
.fold__icon {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 17px;
  color: var(--cyan);
  transition: transform var(--dur) var(--ease);
}
.fold[data-open] .fold__icon { transform: rotate(45deg); }
.fold__panel {
  padding: 0 20px 22px;
  font-size: 15.5px;
  line-height: 1.85;
  color: var(--cyan-soft);
}

.skeleton {
  background-image: linear-gradient(90deg, rgba(61, 220, 223, .1), rgba(61, 220, 223, .3), rgba(61, 220, 223, .1));
  background-size: 200% 100%;
  border-radius: var(--radius);
  animation: skeleton-sweep 1.6s linear infinite;
}

.trace-line {
  stroke-dasharray: 720;
  stroke-dashoffset: 720;
  animation: trace-draw 2.4s var(--ease) forwards;
}

/* ---------- 8. 动效协议 ---------- */
[data-reveal-ready] { opacity: 0; transform: translate3d(0, 18px, 0); }
[data-reveal-ready].is-revealed {
  opacity: 1;
  transform: none;
  transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease);
}

@keyframes skeleton-sweep { to { background-position: -200% 0; } }
@keyframes trace-draw { to { stroke-dashoffset: 0; } }
@keyframes nav-in { from { opacity: 0; transform: translateY(-8px); } to { opacity: 1; transform: none; } }

/* ---------- 9. 响应式 ---------- */
@media (max-width: 1080px) {
  .grid--aside { grid-template-columns: minmax(0, 1fr); }
  .grid--3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .foot-index { grid-template-columns: 1.3fr 1fr; row-gap: 38px; }
}

@media (max-width: 900px) {
  .masthead__inner { grid-template-columns: minmax(0, 1fr) auto; }
  .nav-toggle { display: inline-flex; }
  .nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    display: none;
    padding: 6px var(--gutter) 22px;
    background: rgba(4, 18, 31, .98);
    border-bottom: 1px solid var(--hair-cyan);
    box-shadow: 0 26px 40px -30px rgba(0, 0, 0, .9);
  }
  .nav[data-open] { display: block; animation: nav-in 240ms var(--ease); }
  .nav__list { flex-direction: column; align-items: stretch; gap: 0; }
  .nav__item { border-bottom: 1px solid rgba(110, 136, 153, .18); }
  .nav__link { display: block; padding: 14px 2px; font-size: 17px; }
  .nav__link::after { display: none; }
  .nav__link[aria-current="page"] { color: var(--orange); }
}

@media (max-width: 860px) {
  .grid--2, .grid--split { grid-template-columns: minmax(0, 1fr); }
  .section__head { gap: 8px 18px; }
}

@media (max-width: 640px) {
  .grid--3 { grid-template-columns: minmax(0, 1fr); }
  .foot-index { grid-template-columns: minmax(0, 1fr); row-gap: 32px; }
  .foot-bottom__inner { justify-content: flex-start; }
  .statusbar__code { margin-left: 0; }
  .chapter { grid-template-columns: minmax(46px, auto) minmax(0, 1fr); gap: 14px; }
}

@media (max-width: 560px) {
  .masthead__utility .btn--primary { padding: 8px 12px; font-size: 12.5px; letter-spacing: .06em; }
  .nav-toggle__text { display: none; }
  .brandmark__en { letter-spacing: .22em; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }
  [data-reveal-ready] { opacity: 1; transform: none; }
  .card:hover, .btn:hover { transform: none; }
}