:root {
  --color-surface: #f4f4f3;
  --color-surface-alt: #ebebea;
  --color-surface-deep: #dfdfdd;
  --color-ink: #49453b;
  --color-ink-soft: #706a5c;
  --color-ink-muted: #8a8475;
  --color-line: #d5d4d2;
  --color-primary: #8d722f;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #e6e2d8;
  --color-accent: #593bc4;
  --color-accent-ink: #ffffff;
  --color-highlight: #d8d3eb;
  --color-focus: #522fd0;
  --color-contrast-surface: #201d14;
  --color-contrast-ink: #e7e6e4;
  --color-contrast-line: #4c4942;
  --color-contrast-accent: #8b76d5;
  --overlay-scrim: linear-gradient(180deg, rgba(32, 29, 20, 0.35) 0%, rgba(32, 29, 20, 0.72) 55%, rgba(32, 29, 20, 0.92) 100%);
  --font-heading: "Songti SC", "Source Han Serif SC", "Noto Serif SC", SimSun, serif;
  --font-body: "PingFang SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 12.9px;
  --text-sm: 15.5px;
  --text-base: 17px;
  --text-lg: 20.4px;
  --text-xl: 24.5px;
  --text-2xl: 29.4px;
  --text-3xl: 35.3px;
  --text-4xl: 42.3px;
  --text-display: clamp(34px, 6.5vw, 83px);
  --text-figure: clamp(28px, 4.7vw, 60px);
  --weight-heading: 760;
  --weight-body: 400;
  --leading-body: 1.81;
  --leading-heading: 1.27;
  --tracking-heading: -0.005em;
  --radius-sm: 2px;
  --radius-md: 3px;
  --radius-lg: 4px;
  --radius-pill: 4px;
  --border-thin: 2px;
  --border-thick: 2px;
  --shadow-1: 0 1px 0 rgba(73, 69, 59, 0.12);
  --shadow-2: 0 2px 0 rgba(73, 69, 59, 0.18);
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1100px;
  --measure: 74ch;
  --gutter: 24px;
  --section-y: 80px;
  --section-y-lg: 112px;
}

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

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

body {
  margin: 0;
  background-color: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, h5, h6 {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

p, ul, ol, dl, dd, figure, blockquote { margin: 0; }
ul, ol { padding-left: 1.15em; }
li { line-height: inherit; }

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

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

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

button {
  background: none;
  border: 0;
  cursor: pointer;
}

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

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

[hidden] { display: none !important; }

/* ================= accessibility ================= */
.skip-link {
  position: absolute;
  left: var(--space-2);
  top: -120px;
  z-index: 200;
  padding: 10px 16px;
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border: var(--border-thin) solid var(--color-contrast-accent);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  transition: top .16s ease;
}

.skip-link:focus { top: 12px; }

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

#main-content {
  display: block;
  scroll-margin-top: 130px;
}

#main-content:focus { outline: none; }

/* ================= layout primitives ================= */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

.section {
  padding-top: var(--section-y);
  padding-bottom: var(--section-y);
  background-color: var(--color-surface);
  border-top: var(--border-thick) solid var(--color-line);
}

.section--alt { background-color: var(--color-surface-alt); }

.section--soft {
  background-color: var(--color-primary-soft);
  border-top-color: var(--color-primary);
}

.section--deep {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-top-color: var(--color-primary);
}

.section--deep h1,
.section--deep h2,
.section--deep h3,
.section--deep .section-title,
.section--deep .card-title { color: var(--color-contrast-ink); }

.section--deep p,
.section--deep .lede,
.section--deep .section-lede,
.section--deep .card-body {
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent);
}

.section--deep .section-kicker { color: var(--color-contrast-accent); }
.section--deep .card-meta { color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent); }

.section--tight {
  padding-top: var(--space-6);
  padding-bottom: var(--space-6);
}

.tick-rule {
  height: 12px;
  border-top: var(--border-thick) solid var(--color-primary);
  background-image: repeating-linear-gradient(90deg, var(--color-line) 0 2px, transparent 2px 48px);
  background-repeat: no-repeat;
  background-size: 100% 6px;
  background-position: 0 100%;
}

.section--deep .tick-rule {
  background-image: repeating-linear-gradient(90deg, var(--color-contrast-line) 0 2px, transparent 2px 48px);
}

.grid {
  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-5 { grid-column: span 5; }
.col-6 { grid-column: span 6; }
.col-7 { grid-column: span 7; }
.col-8 { grid-column: span 8; }
.col-12 { grid-column: span 12; }

.stack { display: grid; gap: var(--space-2); }
.stack--lg { gap: var(--space-4); }

/* ================= typography ================= */
.display-title {
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: var(--weight-heading);
  line-height: 1.03;
  letter-spacing: -0.022em;
  color: var(--color-ink);
}

.section--deep .display-title { color: var(--color-contrast-ink); }

.lede,
.section-lede {
  max-width: var(--measure);
  font-size: var(--text-lg);
  line-height: 1.6;
  color: var(--color-ink-soft);
}

.section-head {
  display: grid;
  gap: var(--space-1);
  max-width: var(--measure);
  margin-bottom: var(--space-6);
  padding-left: var(--space-3);
  border-left: var(--border-thick) solid var(--color-primary);
}

.section--deep .section-head { border-left-color: var(--color-contrast-accent); }

.section-kicker {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--color-primary);
}

.section-title {
  font-size: var(--text-3xl);
  line-height: 1.16;
}

.prose { max-width: var(--measure); }

.prose p + p { margin-top: var(--space-2); }

.prose h2 {
  font-size: var(--text-2xl);
  margin-top: var(--space-6);
  margin-bottom: var(--space-2);
}

.prose h3 {
  font-size: var(--text-xl);
  margin-top: var(--space-4);
  margin-bottom: var(--space-1);
}

.prose ul,
.prose ol { margin-top: var(--space-2); margin-bottom: var(--space-2); }

.prose li + li { margin-top: var(--space-1); }

.link-inline,
.prose a {
  color: var(--color-accent);
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
}

.link-inline:hover,
.prose a:hover { color: var(--color-focus); }

.section--deep .link-inline,
.section--deep .prose a { color: var(--color-contrast-accent); }

/* ================= buttons ================= */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  padding: 11px 20px;
  background-color: var(--color-surface);
  color: var(--color-ink);
  border: var(--border-thick) solid var(--color-primary);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-1);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: .02em;
  transition: background-color .18s ease, color .18s ease, border-color .18s ease, transform .18s ease;
}

.btn:hover {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  transform: translateY(-2px);
}

.btn--primary {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
}

.btn--primary:hover {
  background-color: color-mix(in srgb, var(--color-primary) 80%, var(--color-contrast-surface));
  color: var(--color-primary-ink);
}

.btn--accent {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-accent-ink);
}

.btn--accent:hover {
  background-color: color-mix(in srgb, var(--color-accent) 78%, var(--color-contrast-surface));
  color: var(--color-accent-ink);
}

.btn--ghost {
  background-color: transparent;
  border-color: var(--color-ink-soft);
  color: var(--color-ink);
}

.btn--ghost:hover {
  background-color: var(--color-highlight);
  border-color: var(--color-primary);
  color: var(--color-ink);
}

.btn--deep {
  background-color: var(--color-contrast-surface);
  border-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.btn--deep:hover {
  background-color: var(--color-contrast-line);
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-ink);
}

.btn-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  align-items: center;
}

/* ================= tags ================= */
.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  align-items: center;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 8px;
  background-color: var(--color-surface-deep);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  color: var(--color-ink-soft);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .06em;
}

.tag--accent {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-accent-ink);
}

.tag--outline {
  background-color: transparent;
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.section--deep .tag {
  background-color: transparent;
  border-color: var(--color-contrast-line);
  color: color-mix(in srgb, var(--color-contrast-ink) 80%, transparent);
}

.section--deep .tag--accent {
  background-color: var(--color-contrast-accent);
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

/* ================= cards ================= */
.card {
  padding: var(--space-3);
  background-color: var(--color-surface);
  border: var(--border-thick) solid var(--color-line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-1);
  transition: background-color .18s ease, border-color .18s ease, transform .18s ease, box-shadow .18s ease;
}

.card:hover {
  background-color: color-mix(in srgb, var(--color-highlight) 58%, var(--color-surface));
  border-color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-2);
}

.card--deep {
  background-color: var(--color-contrast-surface);
  border-color: var(--color-contrast-line);
  color: var(--color-contrast-ink);
}

.card--deep .card-title { color: var(--color-contrast-ink); }
.card--deep .card-body { color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent); }

.card--deep:hover {
  background-color: color-mix(in srgb, var(--color-contrast-surface) 78%, var(--color-contrast-accent));
  border-color: var(--color-contrast-accent);
}

.card-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-2);
  margin-bottom: var(--space-2);
}

.card-title {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  line-height: 1.3;
}

.card-meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .06em;
  color: var(--color-ink-muted);
}

.card-body {
  font-size: var(--text-base);
  color: var(--color-ink-soft);
}

/* ================= stats ================= */
.stat-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  background-color: var(--color-surface-deep);
  border: var(--border-thick) solid var(--color-line);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.stat-item {
  padding: var(--space-3);
  border-right: var(--border-thin) solid var(--color-line);
}

.stat-item:last-child { border-right: 0; }

.stat-value {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  font-weight: 700;
  line-height: 1;
  color: var(--color-primary);
}

.stat-label {
  display: block;
  margin-top: var(--space-1);
  font-size: var(--text-xs);
  letter-spacing: .1em;
  color: var(--color-ink-muted);
}

.section--deep .stat-strip {
  background-color: color-mix(in srgb, var(--color-contrast-surface) 80%, var(--color-contrast-line));
  border-color: var(--color-contrast-line);
}

.section--deep .stat-item { border-right-color: var(--color-contrast-line); }
.section--deep .stat-value { color: var(--color-contrast-accent); }
.section--deep .stat-label { color: color-mix(in srgb, var(--color-contrast-ink) 68%, transparent); }

/* ================= media frames ================= */
.media-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  background-color: var(--color-surface-deep);
  border: var(--border-thick) solid var(--color-line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-1);
}

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

.media-frame img,
.media-frame svg,
.media-frame .media-layer {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--overlay .media-scrim {
  position: absolute;
  inset: 0;
  background-image: var(--overlay-scrim);
}

.media-frame--overlay .media-title {
  position: absolute;
  left: var(--space-3);
  right: var(--space-3);
  bottom: var(--space-3);
  z-index: 2;
  color: var(--color-contrast-ink);
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  line-height: 1.25;
}

.media-caption {
  margin-top: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .05em;
  color: var(--color-ink-muted);
}

.section--deep .media-caption { color: color-mix(in srgb, var(--color-contrast-ink) 66%, transparent); }

/* ================= breadcrumb ================= */
.breadcrumb {
  background-color: var(--color-surface-alt);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
  margin: 0;
  padding: 0;
  list-style: none;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .08em;
  color: var(--color-ink-muted);
}

.breadcrumb-list li { display: inline-flex; align-items: center; gap: var(--space-1); }

.breadcrumb-list li + li::before {
  content: "/";
  color: var(--color-line);
}

.breadcrumb-list a {
  color: var(--color-ink-soft);
  border-bottom: var(--border-thin) solid transparent;
}

.breadcrumb-list a:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

/* ================= disclosure ================= */
.disclosure {
  background-color: var(--color-surface);
  border: var(--border-thick) solid var(--color-line);
  border-radius: var(--radius-md);
  transition: border-color .18s ease, background-color .18s ease;
}

.disclosure + .disclosure { margin-top: var(--space-2); }
.disclosure:hover { border-color: var(--color-primary); }

.disclosure[data-open] {
  border-color: var(--color-primary);
  background-color: color-mix(in srgb, var(--color-primary-soft) 55%, var(--color-surface));
}

.disclosure-trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  width: 100%;
  padding: var(--space-2) var(--space-3);
  text-align: left;
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  color: var(--color-ink);
  border-radius: var(--radius-sm);
}

.disclosure-trigger:hover { background-color: var(--color-highlight); }

.disclosure-mark {
  position: relative;
  flex: 0 0 auto;
  width: 18px;
  height: 18px;
  border: var(--border-thin) solid var(--color-primary);
  border-radius: var(--radius-sm);
}

.disclosure-mark::before,
.disclosure-mark::after {
  content: "";
  position: absolute;
  background-color: var(--color-primary);
}

.disclosure-mark::before {
  left: 3px;
  right: 3px;
  top: 50%;
  height: 2px;
  transform: translateY(-50%);
}

.disclosure-mark::after {
  top: 3px;
  bottom: 3px;
  left: 50%;
  width: 2px;
  transform: translateX(-50%);
  transition: transform .18s ease;
}

.disclosure[data-open] .disclosure-mark::after { transform: translateX(-50%) scaleY(0); }

.disclosure-panel {
  padding: var(--space-2) var(--space-3) var(--space-3);
  border-top: var(--border-thin) solid var(--color-line);
  color: var(--color-ink-soft);
  font-size: var(--text-base);
  max-width: var(--measure);
}

/* ================= header ================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background-color: var(--color-surface);
  border-bottom: var(--border-thin) solid var(--color-primary);
}

.header-rule {
  height: 12px;
  border-top: var(--border-thick) solid var(--color-primary);
  border-bottom: var(--border-thin) solid var(--color-line);
  background-color: var(--color-surface-alt);
  background-image: repeating-linear-gradient(90deg, var(--color-line) 0 2px, transparent 2px 44px);
  background-repeat: no-repeat;
  background-size: 100% 6px;
  background-position: 0 100%;
}

.header-frame { position: relative; }

.header-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  gap: var(--space-3);
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-2) var(--gutter);
}

.brand-block {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  min-width: 0;
}

.brand-mark {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding-left: 12px;
  border-left: var(--border-thick) solid var(--color-primary);
}

.brand-name {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  line-height: 1.1;
  color: var(--color-ink);
}

.brand-sign {
  font-size: var(--text-xs);
  letter-spacing: .08em;
  color: var(--color-ink-muted);
}

.brand-version,
.footer-version {
  display: flex;
  align-items: center;
  gap: 6px;
  margin: 0;
}

.version-key {
  font-size: var(--text-xs);
  letter-spacing: .1em;
  color: var(--color-ink-muted);
}

.version-val {
  padding: 2px 6px;
  background-color: var(--color-accent);
  color: var(--color-accent-ink);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .08em;
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--space-1);
  justify-self: end;
  padding: 9px 12px;
  background-color: var(--color-surface-alt);
  color: var(--color-ink);
  border: var(--border-thick) solid var(--color-primary);
  border-radius: var(--radius-sm);
  font-size: var(--text-sm);
  font-weight: 600;
  transition: background-color .16s ease;
}

.nav-toggle:hover { background-color: var(--color-highlight); }

.nav-toggle-bars {
  display: inline-flex;
  flex-direction: column;
  gap: 3px;
  width: 18px;
}

.toggle-bar {
  display: block;
  height: 2px;
  background-color: var(--color-primary);
}

.site-nav { justify-self: center; }

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-link {
  display: block;
  padding: 9px 11px;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
  color: var(--color-ink-soft);
  font-size: var(--text-sm);
  font-weight: 600;
  white-space: nowrap;
  transition: background-color .16s ease, color .16s ease, border-color .16s ease;
}

.nav-link:hover {
  background-color: var(--color-highlight);
  border-color: var(--color-line);
  color: var(--color-ink);
}

.nav-link[aria-current="page"] {
  background-color: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-ink);
}

.header-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--space-1);
}

.action-primary {
  display: inline-flex;
  align-items: center;
  padding: 10px 16px;
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  border: var(--border-thick) solid var(--color-primary);
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-1);
  font-size: var(--text-sm);
  font-weight: 600;
  white-space: nowrap;
  transition: background-color .18s ease, border-color .18s ease, transform .18s ease;
}

.action-primary:hover {
  background-color: color-mix(in srgb, var(--color-primary) 78%, var(--color-contrast-surface));
  border-color: color-mix(in srgb, var(--color-primary) 78%, var(--color-contrast-surface));
  transform: translateY(-2px);
}

.action-quiet {
  padding: 10px 12px;
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  color: var(--color-ink-soft);
  font-size: var(--text-sm);
  white-space: nowrap;
  transition: background-color .16s ease, color .16s ease, border-color .16s ease;
}

.action-quiet:hover {
  background-color: var(--color-highlight);
  border-color: var(--color-primary);
  color: var(--color-ink);
}

.header-progress {
  position: absolute;
  left: 0;
  bottom: -2px;
  z-index: 2;
  width: 0;
  height: 3px;
  background-color: var(--color-accent);
}

/* ================= float bar ================= */
.float-bar {
  position: fixed;
  left: 50%;
  bottom: var(--space-2);
  z-index: 90;
  transform: translate(-50%, 26px);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: transform .2s ease, opacity .2s ease, visibility .2s;
}

.float-bar[data-visible] {
  transform: translate(-50%, 0);
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.float-bar-inner {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: 10px var(--space-2);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border: var(--border-thick) solid var(--color-contrast-line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-2);
}

.float-bar-label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .14em;
  color: color-mix(in srgb, var(--color-contrast-ink) 68%, transparent);
}

.float-link {
  padding: 7px 14px;
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  font-weight: 600;
  white-space: nowrap;
  transition: color .16s ease, border-color .16s ease, background-color .16s ease;
}

.float-link:hover {
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-accent);
}

.float-link--primary {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-accent-ink);
}

.float-link--primary:hover {
  background-color: color-mix(in srgb, var(--color-accent) 80%, var(--color-contrast-surface));
  color: var(--color-accent-ink);
}

/* ================= footer ================= */
.site-footer {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-top: var(--border-thick) solid var(--color-primary);
}

.footer-rule {
  height: 14px;
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
  background-color: var(--color-contrast-surface);
  background-image: repeating-linear-gradient(90deg, var(--color-contrast-line) 0 2px, transparent 2px 44px);
  background-repeat: no-repeat;
  background-size: 100% 7px;
  background-position: 0 100%;
}

.footer-inner {
  display: grid;
  grid-template-columns: minmax(0, 4fr) minmax(0, 8fr);
  gap: var(--space-6);
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-6) var(--gutter);
}

.footer-brand-name {
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  font-weight: var(--weight-heading);
  color: var(--color-contrast-ink);
}

.footer-brand-sign {
  margin-top: 6px;
  font-size: var(--text-xs);
  letter-spacing: .12em;
  color: var(--color-contrast-accent);
}

.footer-note {
  margin-top: var(--space-2);
  max-width: 34ch;
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 74%, transparent);
}

.footer-version { margin-top: var(--space-3); }

.site-footer .version-key { color: color-mix(in srgb, var(--color-contrast-ink) 68%, transparent); }

.footer-columns {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--space-3);
}

.footer-col {
  padding-left: var(--space-2);
  border-left: var(--border-thin) solid var(--color-contrast-line);
}

.footer-col-title {
  padding-top: 10px;
  border-top: var(--border-thin) solid var(--color-primary);
  font-family: var(--font-heading);
  font-size: var(--text-base);
  font-weight: var(--weight-heading);
  color: var(--color-contrast-ink);
}

.footer-col-list {
  display: grid;
  gap: var(--space-1);
  margin: var(--space-2) 0 0;
  padding: 0;
  list-style: none;
}

.footer-col-list a {
  display: inline-block;
  padding-bottom: 1px;
  border-bottom: var(--border-thin) solid transparent;
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, transparent);
  transition: color .16s ease, border-color .16s ease;
}

.footer-col-list a:hover {
  color: var(--color-contrast-accent);
  border-bottom-color: var(--color-contrast-accent);
}

.footer-base {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-2);
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-3) var(--gutter) var(--space-6);
  border-top: var(--border-thin) solid var(--color-contrast-line);
  font-size: var(--text-xs);
  color: color-mix(in srgb, var(--color-contrast-ink) 66%, transparent);
}

.footer-legal {
  font-family: var(--font-mono);
  letter-spacing: .06em;
}

.footer-legal-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  margin: 0;
  padding: 0;
  list-style: none;
}

.footer-legal-links a {
  padding-bottom: 2px;
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
  color: var(--color-contrast-ink);
  font-size: var(--text-xs);
  transition: color .16s ease, border-color .16s ease;
}

.footer-legal-links a:hover {
  color: var(--color-contrast-accent);
  border-bottom-color: var(--color-contrast-accent);
}

.footer-contact {
  flex: 1 1 320px;
  max-width: 62ch;
  line-height: 1.75;
}

/* ================= responsive ================= */
@media (max-width: 1040px) {
  .header-inner { grid-template-columns: minmax(0, 1fr) auto; }

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

  .site-nav,
  .header-actions { display: none; grid-column: 1 / -1; }

  .site-nav[data-open] {
    display: block;
    justify-self: stretch;
    padding-top: var(--space-2);
    border-top: var(--border-thin) solid var(--color-line);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .nav-link {
    padding: 13px 12px;
    border: 0;
    border-bottom: var(--border-thin) solid var(--color-line);
    border-radius: 0;
  }

  .nav-link:hover { background-color: var(--color-highlight); }
  .nav-link[aria-current="page"] { border-bottom-color: var(--color-primary); }

  .site-nav[data-open] ~ .header-actions {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-start;
    padding-top: var(--space-2);
    border-top: var(--border-thin) solid var(--color-line);
  }

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

@media (max-width: 900px) {
  .grid { grid-template-columns: repeat(6, minmax(0, 1fr)); }
  .col-3 { grid-column: span 3; }
  .col-4 { grid-column: span 3; }
  .col-5,
  .col-6,
  .col-7,
  .col-8,
  .col-12 { grid-column: span 6; }

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

  .section-title { font-size: var(--text-2xl); }
}

@media (max-width: 720px) {
  .section {
    padding-top: var(--space-6);
    padding-bottom: var(--space-6);
  }

  .section-head { margin-bottom: var(--space-4); }
  .lede,
  .section-lede { font-size: var(--text-base); }
  .section--deep .display-title { font-size: var(--text-3xl); }

  .stat-item {
    border-right: 0;
    border-bottom: var(--border-thin) solid var(--color-line);
  }

  .stat-item:last-child { border-bottom: 0; }

  .float-bar-inner { gap: var(--space-1); padding: 8px 10px; }
  .float-bar-label { display: none; }
  .float-link { padding: 8px 12px; }
}

@media (max-width: 560px) {
  .grid { grid-template-columns: minmax(0, 1fr); }
  .col-3,
  .col-4,
  .col-5,
  .col-6,
  .col-7,
  .col-8,
  .col-12 { grid-column: 1 / -1; }

  .brand-version { display: none; }
  .brand-sign { font-size: var(--text-xs); letter-spacing: .04em; }

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

  .footer-col {
    padding-left: 0;
    border-left: 0;
  }

  .footer-base { flex-direction: column; align-items: flex-start; }
}

/* ================= reduced motion ================= */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
  }

  .card:hover,
  .btn:hover,
  .action-primary:hover { transform: none; }

  .float-bar { transition: none; }
  .skip-link { transition: none; }
}