/* ============================================================
   启博中心 · 共享样式表 /assets/site.css
   极简文字建筑 + 双通道对照 + 坐标索引
   ============================================================ */

/* ---------- 0. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

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

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

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

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

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

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

[hidden] { display: none !important; }

/* ---------- 1. Design tokens ---------- */
:root {
  --ink: #0B1B33;
  --ink-2: #13294B;
  --signal: #00E5C7;
  --signal-deep: #00A38C;
  --alert: #FF7A45;
  --ochre: #C49A6C;
  --ochre-deep: #8C6A3F;
  --paper: #EFE7D8;
  --text: #D6E3EE;
  --muted: #93A7B8;
  --hi: #F7FBFD;

  --line: rgba(214, 227, 238, 0.14);
  --line-soft: rgba(214, 227, 238, 0.07);
  --line-signal: rgba(0, 229, 199, 0.45);
  --line-paper: rgba(11, 27, 51, 0.16);

  --shadow: 0 1px 0 rgba(0, 229, 199, 0.07), 0 22px 48px -34px rgba(0, 0, 0, 0.85);

  --font-display: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", Georgia, "Times New Roman", serif;
  --font-body: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Inter, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "IBM Plex Mono", "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;

  --shell: 1280px;
  --gutter: clamp(16px, 4vw, 24px);
  --radius: 2px;
  --t: 180ms;
}

/* ---------- 2. Base typography ---------- */
body {
  background: var(--ink);
  color: var(--text);
  font-family: var(--font-body);
  font-size: clamp(16px, 0.35vw + 15px, 19px);
  font-weight: 400;
  line-height: 1.85;
  letter-spacing: 0.005em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

#main-content { scroll-margin-top: 88px; }

:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 2px;
}

.display {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2.2rem, 5.6vw, 5rem);
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--hi);
  text-shadow: 1px 0 0 rgba(255, 122, 69, 0.32), -1px 0 0 rgba(0, 229, 199, 0.16);
}

.h2 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.5rem, 2.6vw, 2.5rem);
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--hi);
}

.h3 {
  font-size: clamp(1.05rem, 1.4vw, 1.25rem);
  font-weight: 600;
  line-height: 1.5;
  color: var(--hi);
}

.lede {
  font-size: clamp(1rem, 1.2vw, 1.15rem);
  line-height: 1.8;
  color: var(--text);
  max-width: 38em;
}

.kicker {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--signal);
}

.kicker::before {
  content: "";
  width: 18px;
  height: 1px;
  background: currentColor;
  flex: 0 0 auto;
}

.prose { max-width: 38em; }
.prose p + p { margin-top: 1.1em; }
.prose strong { color: var(--hi); font-weight: 600; }

.u-link {
  position: relative;
  display: inline-block;
  transition: color var(--t) ease;
}

.u-link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform var(--t) ease;
}

.u-link:hover { color: var(--signal); }
.u-link:hover::after,
.u-link:focus-visible::after { transform: scaleX(1); }

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.hairline {
  height: 1px;
  border: 0;
  margin: 0;
  background: var(--line);
}

/* ---------- 3. Layout ---------- */
.shell {
  width: min(var(--shell), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
}

.section { padding-block: clamp(48px, 7vw, 110px); }
.section--tight { padding-block: clamp(32px, 4vw, 64px); }

.section__head {
  display: grid;
  gap: 14px;
  max-width: 44rem;
  margin-bottom: clamp(28px, 4vw, 56px);
}

.grid { display: grid; gap: clamp(20px, 3vw, 40px); }
.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--split {
  display: grid;
  grid-template-columns: 5fr 7fr;
  gap: clamp(24px, 4vw, 64px);
  align-items: start;
}

/* ---------- 4. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 20px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-size: 0.86rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  line-height: 1.2;
  transition: background var(--t) ease, color var(--t) ease, border-color var(--t) ease;
}

.btn--signal {
  background: var(--signal);
  border-color: var(--signal);
  color: #04211C;
}

.btn--signal:hover { background: #5CF2DE; border-color: #5CF2DE; }

.btn--outline {
  border-color: var(--line-signal);
  color: var(--signal);
  background: transparent;
}

.btn--outline:hover { background: rgba(0, 229, 199, 0.1); border-color: var(--signal); color: var(--hi); }

.btn--ochre {
  border-color: rgba(196, 154, 108, 0.6);
  color: var(--ochre);
  background: transparent;
}

.btn--ochre:hover { background: rgba(196, 154, 108, 0.14); color: var(--paper); }

.btn--quiet {
  border-color: var(--line);
  color: var(--text);
  background: transparent;
}

.btn--quiet:hover { border-color: var(--muted); background: rgba(214, 227, 238, 0.06); }

/* ---------- 5. Breadcrumbs ---------- */
.crumbs {
  padding-block: 14px;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: var(--muted);
}

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

.crumbs__item { display: inline-flex; align-items: center; gap: 8px; }

.crumbs__item + .crumbs__item::before {
  content: "/";
  color: rgba(147, 167, 184, 0.5);
}

.crumbs__item a { transition: color var(--t) ease; }
.crumbs__item a:hover { color: var(--signal); }

/* ---------- 6. Panels ---------- */
.panel {
  background: var(--ink-2);
  border: 1px solid var(--line);
  padding: clamp(20px, 3vw, 36px);
  box-shadow: var(--shadow);
}

.panel--grid {
  background-color: var(--ink-2);
  background-image:
    linear-gradient(rgba(0, 229, 199, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 199, 0.07) 1px, transparent 1px);
  background-size: 30px 30px;
}

.panel--paper {
  background: var(--paper);
  background-image: repeating-linear-gradient(0deg, rgba(11, 27, 51, 0.05) 0 1px, transparent 1px 4px);
  border: 1px solid var(--line-paper);
  border-left: 3px solid var(--ochre);
  color: #33465B;
  box-shadow: var(--shadow);
}

.panel--paper .h2,
.panel--paper .h3 { color: var(--ink); }

.panel--paper .lede,
.panel--paper .prose { color: #33465B; }

/* ---------- 7. Legend index ---------- */
.legend {
  display: grid;
  border-top: 1px solid var(--line);
}

.legend__row {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 14px;
  align-items: baseline;
  padding: 14px 8px;
  border-bottom: 1px solid var(--line);
  transition: background var(--t) ease;
}

.legend__row:hover { background: rgba(214, 227, 238, 0.06); }

.legend__coord {
  position: relative;
  padding-left: 14px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  color: var(--muted);
}

.legend__coord::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 6px;
  height: 6px;
  margin-top: -3px;
  border-radius: 50%;
  border: 1px solid var(--muted);
  transition: background var(--t) ease, border-color var(--t) ease;
}

.legend__row:hover .legend__coord::before {
  background: var(--signal);
  border-color: var(--signal);
}

.legend__text { display: block; }

/* ---------- 8. Route line ---------- */
.route {
  position: relative;
  display: grid;
  padding-left: 26px;
}

.route::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 12px;
  bottom: 12px;
  width: 1px;
  background: linear-gradient(180deg, var(--signal), rgba(0, 229, 199, 0.12) 70%, transparent);
}

.route__step {
  position: relative;
  padding: 16px 0;
}

.route__node {
  position: absolute;
  left: -26px;
  top: 22px;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  border: 1px solid var(--signal);
  background: var(--ink);
}

.route__node::after {
  content: "";
  position: absolute;
  inset: 3px;
  border-radius: 50%;
  background: var(--signal);
}

.route__name {
  display: block;
  font-weight: 600;
  color: var(--hi);
}

.route__note {
  display: block;
  font-size: 0.9rem;
  color: var(--muted);
}

/* ---------- 9. Compare table ---------- */
.compare {
  width: 100%;
  border-top: 1px solid var(--line);
}

.compare__row {
  display: grid;
  grid-template-columns: minmax(110px, 0.9fr) 1.4fr 1.4fr;
  border-bottom: 1px solid var(--line);
}

.compare__dim {
  padding: 16px 12px;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  color: var(--muted);
}

.compare__old {
  padding: 16px 12px;
  background: rgba(239, 231, 216, 0.06);
  border-left: 1px solid var(--line);
  color: #E6DCC8;
}

.compare__new {
  padding: 16px 12px;
  background: rgba(0, 229, 199, 0.06);
  border-left: 1px solid var(--line-signal);
  color: var(--hi);
}

/* ---------- 10. Switch field (native checkbox) ---------- */
.switch-field {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.switch-field__input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

.switch-field__label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.08em;
  color: var(--muted);
  cursor: pointer;
  transition: border-color var(--t) ease, color var(--t) ease, background var(--t) ease;
}

.switch-field__label:hover { color: var(--text); border-color: var(--muted); }

.switch-field__input:checked + .switch-field__label {
  border-color: var(--signal);
  color: var(--hi);
  background-color: rgba(0, 229, 199, 0.08);
  background-image:
    linear-gradient(rgba(0, 229, 199, 0.09) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 199, 0.09) 1px, transparent 1px);
  background-size: 14px 14px;
}

.switch-field__input:focus-visible + .switch-field__label {
  outline: 2px solid var(--signal);
  outline-offset: 2px;
}

/* ---------- 11. Figure / responsive image containers ---------- */
.figure { display: block; margin: 0; }

.figure__media {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background: linear-gradient(180deg, var(--ink-2), #0E2140);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.figure__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.figure__media--4x3 { aspect-ratio: 4 / 3; }
.figure__media--1x1 { aspect-ratio: 1 / 1; }
.figure__media--21x9 { aspect-ratio: 21 / 9; }

.figure--paper .figure__media {
  background: linear-gradient(180deg, #F4EEE2, var(--paper));
  border-color: var(--line-paper);
}

.figure--paper .figure__media::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(0deg, rgba(11, 27, 51, 0.06) 0 1px, transparent 1px 4px);
  pointer-events: none;
}

.figure--grid .figure__media::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0, 229, 199, 0.14) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 199, 0.14) 1px, transparent 1px);
  background-size: 34px 34px;
  pointer-events: none;
}

.figure__cap {
  margin-top: 12px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--muted);
}

/* ---------- 12. Stat / Tag / Arch-tag ---------- */
.stat { display: grid; gap: 4px; }

.stat__num {
  font-family: var(--font-mono);
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--hi);
}

.stat__label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 9px;
  border: 1px solid var(--line);
  background: rgba(214, 227, 238, 0.04);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  color: var(--muted);
}

.tag--signal {
  border-color: var(--line-signal);
  background: rgba(0, 229, 199, 0.08);
  color: var(--signal);
}

.tag--alert {
  border-color: rgba(255, 122, 69, 0.45);
  background: rgba(255, 122, 69, 0.08);
  color: var(--alert);
}

.arch-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 4px 10px;
  border: 1px dashed rgba(196, 154, 108, 0.5);
  background: rgba(196, 154, 108, 0.07);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ochre);
}

/* ---------- 13. Fold (details / summary) ---------- */
.fold { border-top: 1px solid var(--line); }

.fold__head {
  display: flex;
  gap: 14px;
  align-items: baseline;
  padding: 18px 4px;
  list-style: none;
  cursor: pointer;
  font-weight: 500;
  color: var(--hi);
  transition: color var(--t) ease;
}

.fold__head::-webkit-details-marker { display: none; }

.fold__head::before {
  content: "+";
  font-family: var(--font-mono);
  font-size: 1rem;
  line-height: 1;
  color: var(--signal);
}

.fold[open] .fold__head::before { content: "\2013"; }

.fold__head:hover { color: var(--signal); }

.fold__body {
  max-width: 38em;
  padding: 0 4px 22px;
  border-bottom: 1px solid var(--line);
  color: var(--text);
}

/* ---------- 14. Header : command bar ---------- */
.skip-link {
  position: absolute;
  left: var(--gutter);
  top: -72px;
  z-index: 120;
  padding: 10px 16px;
  border-radius: var(--radius);
  background: var(--signal);
  color: #04211C;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  transition: top var(--t) ease;
}

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

.cmd-bar {
  position: sticky;
  top: 0;
  z-index: 80;
  background: var(--ink);
  border-bottom: 1px solid var(--ink-2);
  box-shadow: 0 1px 0 rgba(0, 229, 199, 0.08);
}

.cmd-bar__inner {
  display: flex;
  align-items: center;
  gap: clamp(10px, 1.6vw, 26px);
  width: min(var(--shell), calc(100% - var(--gutter) * 2));
  min-height: 66px;
  margin-inline: auto;
}

.brand {
  display: inline-flex;
  align-items: baseline;
  gap: 10px;
  flex: 0 0 auto;
  padding-block: 8px;
  padding-right: clamp(10px, 1.4vw, 22px);
  border-right: 1px solid var(--ink-2);
}

.brand__mark {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 1.12rem;
  letter-spacing: 0.02em;
  color: var(--hi);
  transition: color var(--t) ease;
}

.brand:hover .brand__mark { color: var(--signal); }

.brand__ver {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  color: var(--ochre);
}

.nav {
  flex: 1 1 auto;
  min-width: 0;
}

.nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.nav__list::-webkit-scrollbar { display: none; }

.nav__item { flex: 0 0 auto; }

.nav__link {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 9px 10px;
  border-left: 2px solid transparent;
  font-size: 0.84rem;
  white-space: nowrap;
  color: var(--text);
  transition: background var(--t) ease, border-color var(--t) ease, color var(--t) ease;
}

.nav__link:hover {
  background: rgba(214, 227, 238, 0.06);
  color: var(--hi);
}

.nav__coord {
  position: relative;
  padding-left: 14px;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: var(--muted);
  transition: color var(--t) ease;
}

.nav__coord::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 6px;
  height: 6px;
  margin-top: -3px;
  border-radius: 50%;
  border: 1px solid var(--muted);
  transition: background var(--t) ease, border-color var(--t) ease;
}

.nav__link:hover .nav__coord::before {
  background: var(--signal);
  border-color: var(--signal);
}

.nav__label { transition: color var(--t) ease; }

.nav__link[aria-current="page"] {
  border-left-color: var(--signal);
  background: rgba(0, 229, 199, 0.1);
  color: var(--hi);
}

.nav__link[aria-current="page"] .nav__coord { color: var(--signal); }

.nav__link[aria-current="page"] .nav__coord::before {
  background: var(--signal);
  border-color: var(--signal);
  box-shadow: 0 0 0 3px rgba(0, 229, 199, 0.15);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 9px;
  padding: 9px 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--text);
  transition: border-color var(--t) ease, color var(--t) ease, background var(--t) ease;
}

.nav-toggle::before {
  content: "";
  width: 14px;
  height: 1px;
  background: currentColor;
  box-shadow: 0 -4px 0 currentColor, 0 4px 0 currentColor;
}

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

.nav-toggle[aria-expanded="true"] {
  border-color: var(--signal);
  color: var(--signal);
  background: rgba(0, 229, 199, 0.08);
}

.cmd-bar__action {
  position: relative;
  flex: 0 0 auto;
}

.switch-btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 9px 14px;
  border: 1px solid var(--line-signal);
  border-radius: var(--radius);
  background: rgba(0, 229, 199, 0.08);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  color: var(--signal);
  transition: background var(--t) ease, border-color var(--t) ease, color var(--t) ease;
}

.switch-btn:hover {
  background: rgba(0, 229, 199, 0.16);
  border-color: var(--signal);
  color: var(--hi);
}

.switch-btn__dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--signal);
  box-shadow: 0 0 0 3px rgba(0, 229, 199, 0.18);
}

.switch-btn__text { display: inline; }

.switch-panel {
  position: absolute;
  top: calc(100% + 12px);
  right: 0;
  width: min(268px, 80vw);
  padding: 14px 16px;
  background: var(--ink);
  border: 1px solid var(--ink-2);
  border-left: 2px solid var(--alert);
  box-shadow: 0 26px 52px -32px rgba(0, 0, 0, 0.95);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px);
  transition: opacity var(--t) ease, transform var(--t) ease, visibility var(--t) ease;
}

.cmd-bar__action:hover .switch-panel,
.cmd-bar__action:focus-within .switch-panel {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.switch-panel__step {
  display: flex;
  gap: 10px;
  align-items: baseline;
  font-size: 0.82rem;
  line-height: 1.55;
  color: var(--text);
}

.switch-panel__step + .switch-panel__step {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px solid var(--line);
}

.switch-panel__num {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: var(--alert);
}

.cmd-bar__progress {
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, var(--signal), var(--alert));
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 90ms linear;
}

/* ---------- 15. Footer ---------- */
.site-footer {
  margin-top: clamp(64px, 9vw, 140px);
  background: var(--ink);
  border-top: 1px solid var(--ink-2);
  color: var(--text);
}

.footer__grid {
  display: grid;
  grid-template-columns: 1fr 1.25fr 1.45fr;
  gap: clamp(24px, 3.4vw, 56px);
  width: min(var(--shell), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  padding-block: clamp(40px, 6vw, 80px);
}

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

.footer-col + .footer-col {
  border-left: 1px solid var(--line);
  padding-left: clamp(20px, 2.6vw, 44px);
}

.footer-col__title {
  display: flex;
  align-items: center;
  gap: 9px;
  margin-bottom: 18px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--signal);
}

.footer-col__title::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--signal);
  flex: 0 0 auto;
}

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

.footer-links--grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  column-gap: 20px;
}

.footer-links a,
.footer-links span {
  font-size: 0.92rem;
  line-height: 1.6;
}

.footer-contact { gap: 12px; }
.footer-contact li { display: grid; gap: 2px; }

.footer-contact__key {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  color: var(--muted);
}

.footer-contact__val {
  color: var(--text);
  font-size: 0.92rem;
  word-break: break-word;
}

.footer-col .btn { margin-top: 20px; }

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 28px;
  width: min(var(--shell), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  padding-block: 18px;
  border-top: 1px solid var(--line);
  font-size: 0.82rem;
  color: var(--muted);
}

.footer-legal__list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
}

.footer-legal__list a { color: var(--text); }

.footer-legal__note {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.1em;
  color: var(--ochre);
}

.footer-handoff {
  height: 8px;
  background: linear-gradient(90deg, var(--ink-2) 0%, var(--signal) 32%, var(--ochre) 66%, var(--paper) 100%);
  opacity: 0.9;
}

.footer-base {
  background: var(--paper);
  background-image: repeating-linear-gradient(0deg, rgba(11, 27, 51, 0.045) 0 1px, transparent 1px 4px);
  color: #22333F;
}

.footer-base__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 24px;
  width: min(var(--shell), calc(100% - var(--gutter) * 2));
  margin-inline: auto;
  padding-block: 16px 20px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
}

.footer-base__brand {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 0.9rem;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.footer-base__icp { color: #3D5163; }

.footer-base__region { color: var(--ochre-deep); }

.footer-base__region::before {
  content: "\25C6";
  margin-right: 6px;
  font-size: 0.6rem;
}

.footer-base__copy {
  margin-left: auto;
  color: #5A6B7A;
}

/* ---------- 16. Responsive ---------- */
@media (max-width: 1080px) {
  .nav__link { font-size: 0.8rem; padding: 9px 8px; }
}

@media (max-width: 900px) {
  .grid--3,
  .grid--4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }

  .grid--split { grid-template-columns: 1fr; }
}

@media (max-width: 880px) {
  .cmd-bar__inner { min-height: 60px; gap: 10px; }

  .brand {
    border-right: 0;
    padding-right: 0;
  }

  .nav-toggle {
    display: inline-flex;
    margin-left: auto;
  }

  .cmd-bar__action { margin-left: 8px; }

  .nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    display: none;
    padding: 10px var(--gutter) 18px;
    background: var(--ink);
    border-bottom: 1px solid var(--ink-2);
    box-shadow: 0 34px 64px -44px rgba(0, 0, 0, 1);
  }

  .nav[data-open] { display: block; }

  .nav__list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 2px;
    overflow: visible;
  }

  .nav__link { padding: 12px 10px; font-size: 0.9rem; }

  .footer__grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .footer-col + .footer-col {
    border-left: 0;
    border-top: 1px solid var(--line);
    padding-left: 0;
    padding-top: 28px;
  }

  .footer-legal__note { margin-left: 0; }
  .footer-base__copy { margin-left: 0; }
}

@media (max-width: 640px) {
  .grid--2,
  .grid--3,
  .grid--4 { grid-template-columns: 1fr; }

  .compare__row { grid-template-columns: 1fr; }

  .compare__old,
  .compare__new {
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .footer-links--grid { grid-template-columns: 1fr; }

  .switch-panel { width: min(268px, 86vw); }
}

@media (max-width: 420px) {
  .nav__list { grid-template-columns: 1fr; }

  .brand__ver { display: none; }

  .switch-btn { padding: 9px 11px; }
}

@media (hover: none) {
  .cmd-bar__action:hover .switch-panel {
    opacity: 0;
    visibility: hidden;
  }
}

/* ---------- 17. Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  .cmd-bar__progress { transition: none; }
}