:root {
  --color-surface: #fdfdfd;
  --color-surface-alt: #f4f4f4;
  --color-surface-deep: #e7e8e8;
  --color-ink: #434c4c;
  --color-ink-soft: #657171;
  --color-ink-muted: #7a8585;
  --color-line: #dcdddd;
  --color-primary: #0b8483;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #dbecec;
  --color-accent: #e41b27;
  --color-accent-ink: #ffffff;
  --color-highlight: #f8d4d6;
  --color-focus: #e70e1a;
  --color-contrast-surface: #102323;
  --color-contrast-ink: #e4e7e7;
  --color-contrast-line: #3f4e4e;
  --color-contrast-accent: #ea525b;
  --overlay-scrim: linear-gradient(180deg, rgba(16, 35, 35, 0.35) 0%, rgba(16, 35, 35, 0.72) 55%, rgba(16, 35, 35, 0.92) 100%);
  --font-heading: ui-monospace, SFMono-Regular, Menlo, Consolas, "PingFang SC", monospace;
  --font-body: "PingFang SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --text-xs: 10.4px;
  --text-sm: 13.9px;
  --text-base: 16px;
  --text-lg: 21.3px;
  --text-xl: 28.4px;
  --text-2xl: 37.9px;
  --text-3xl: 50.5px;
  --text-4xl: 67.3px;
  --text-display: clamp(46px, 9.5vw, 121px);
  --text-figure: clamp(38px, 6.8vw, 87px);
  --weight-heading: 618;
  --weight-body: 400;
  --leading-body: 1.69;
  --leading-heading: 1.24;
  --tracking-heading: 0.004em;
  --radius-sm: 372px;
  --radius-md: 490px;
  --radius-lg: 607px;
  --radius-pill: 999px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: 0 0 0 1px rgba(228, 27, 39, 0.35);
  --shadow-2: 0 0 28px rgba(228, 27, 39, 0.35);
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1180px;
  --measure: 72ch;
  --gutter: 24px;
  --section-y: 64px;
  --section-y-lg: 90px;
}

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

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

body {
  margin: 0;
  background: 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;
}

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

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 { margin: 0 0 var(--space-3); }

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

button { font: inherit; }

a {
  color: var(--color-primary);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: color .16s ease, text-decoration-color .16s ease, text-decoration-thickness .16s ease;
}

a:hover {
  color: var(--color-accent);
  text-decoration-thickness: 2px;
  text-decoration-color: var(--color-accent);
}

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

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

/* ---------- layout primitives ---------- */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--space-3);
}

.container--wide { max-width: calc(var(--container) + var(--space-8)); }
.container--flush { padding: 0; }

.section { padding: var(--section-y) 0; }
.section--lg { padding: var(--section-y-lg) 0; }
.section--tight { padding: var(--space-4) 0; }
.section--deep { background: var(--color-surface-alt); }
.section--drawer {
  background: var(--color-surface-deep);
  border-top: var(--border-thin) solid var(--color-line);
  border-bottom: var(--border-thin) solid var(--color-line);
}

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

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

.section__index {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .26em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-1);
}

.section--contrast .section__index { color: var(--color-contrast-accent); }

.section__title { font-size: var(--text-2xl); }
.section__sub {
  margin-top: var(--space-2);
  max-width: var(--measure);
  color: var(--color-ink-soft);
  font-size: var(--text-base);
}
.section--contrast .section__sub { color: color-mix(in srgb, var(--color-contrast-ink) 78%, transparent); }

.rule-double {
  height: 5px;
  border-top: var(--border-thin) solid var(--color-line);
  border-bottom: var(--border-thin) solid var(--color-line);
  margin: var(--space-6) 0;
}

.rule-dotted {
  border: 0;
  border-top: var(--border-thin) dotted var(--color-line);
  margin: var(--space-4) 0;
}

/* ---------- grid ---------- */
.grid { display: grid; gap: var(--space-3); }
.grid--12 { grid-template-columns: repeat(12, minmax(0, 1fr)); }
.grid--split { grid-template-columns: repeat(12, minmax(0, 1fr)); }

/* ---------- skip link ---------- */
.skip-link {
  position: absolute;
  top: var(--space-1);
  left: var(--space-3);
  z-index: 90;
  display: inline-block;
  padding: 6px var(--space-3);
  border-radius: var(--radius-pill);
  background: var(--color-accent);
  color: var(--color-accent-ink);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  letter-spacing: .08em;
  text-decoration: none;
  transform: translateY(-220%);
  transition: transform .18s ease;
}

.skip-link:focus {
  transform: translateY(0);
  color: var(--color-accent-ink);
  text-decoration: none;
}

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: color-mix(in srgb, var(--color-contrast-surface) 84%, transparent);
  color: var(--color-contrast-ink);
  border-bottom: var(--border-thin) dashed var(--color-contrast-line);
  backdrop-filter: blur(7px);
  -webkit-backdrop-filter: blur(7px);
  transition: background-color .2s ease, color .2s ease, border-color .2s ease;
}

.site-header.is-scrolled {
  background: var(--color-surface);
  color: var(--color-ink);
  border-bottom: var(--border-thin) dotted var(--color-line);
}

.site-header__inner {
  position: relative;
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-2) var(--space-3);
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

/* brand */
.brand { flex: none; }

.brand__link {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  color: inherit;
  text-decoration: none;
}

.brand__link:hover { color: inherit; text-decoration: none; }

.brand__mark {
  position: relative;
  display: block;
  flex: none;
  width: 34px;
  height: 34px;
  border-radius: var(--radius-pill);
  background: linear-gradient(140deg, var(--color-primary) 0%, color-mix(in srgb, var(--color-primary) 45%, var(--color-contrast-surface)) 100%);
  box-shadow: inset 0 0 0 1px color-mix(in srgb, #ffffff 55%, transparent);
}

.brand__mark::after {
  content: "";
  position: absolute;
  top: 5px;
  right: 5px;
  width: 8px;
  height: 8px;
  border-radius: var(--radius-pill);
  background: var(--color-accent);
}

.brand__text { display: block; }

.brand__name {
  display: block;
  font-family: var(--font-heading);
  font-size: var(--text-base);
  font-weight: var(--weight-heading);
  letter-spacing: .07em;
  line-height: 1.2;
}

.brand__sub {
  display: block;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .18em;
  line-height: 1.4;
  opacity: .7;
}

/* nav */
.site-nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: 6px;
}

.site-nav__link {
  display: inline-block;
  padding: 6px var(--space-2);
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid color-mix(in srgb, currentColor 28%, transparent);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  letter-spacing: .05em;
  color: inherit;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color .16s ease, color .16s ease, border-color .16s ease;
}

.site-nav__link:hover,
.site-nav__link:focus-visible {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
  text-decoration: none;
}

.site-nav__link[aria-current="page"] {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
  box-shadow: inset 0 0 0 1px color-mix(in srgb, #ffffff 42%, transparent);
  text-decoration: none;
}

/* status bar */
.statusbar {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px var(--space-2);
  border-radius: var(--radius-pill);
  border: var(--border-thin) dashed color-mix(in srgb, currentColor 34%, transparent);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .14em;
  line-height: 1.2;
  white-space: nowrap;
}

.statusbar__dot {
  flex: none;
  width: 8px;
  height: 8px;
  border-radius: 2px;
  background: var(--color-accent);
  box-shadow: var(--shadow-2);
}

.statusbar__label { opacity: .8; }

.statusbar__track {
  display: block;
  width: 52px;
  height: 6px;
  border-radius: var(--radius-pill);
  background: color-mix(in srgb, currentColor 20%, transparent);
  overflow: hidden;
}

.statusbar__fill {
  display: block;
  height: 100%;
  width: 70%;
  border-radius: var(--radius-pill);
  background: var(--color-primary);
  transition: width .22s ease, background-color .22s ease;
}

.statusbar:hover .statusbar__fill,
.statusbar:focus-within .statusbar__fill {
  width: 100%;
  background: var(--color-accent);
}

.statusbar__value { opacity: .9; }

/* toggle */
.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--space-1);
  margin-left: auto;
  padding: 6px var(--space-2) 6px 10px;
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid color-mix(in srgb, currentColor 32%, transparent);
  background: transparent;
  color: inherit;
  cursor: pointer;
  transition: background-color .16s ease, color .16s ease, border-color .16s ease;
}

.nav-toggle:hover {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
}

.nav-toggle[aria-expanded="true"] {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
}

.nav-toggle__bars {
  display: grid;
  gap: 3px;
  width: 16px;
}

.nav-toggle__bars span {
  display: block;
  height: 2px;
  border-radius: var(--radius-pill);
  background: currentColor;
}

.nav-toggle__text {
  font-family: var(--font-heading);
  font-size: var(--text-xs);
  letter-spacing: .14em;
}

/* ---------- pills & buttons ---------- */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px var(--space-2);
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid color-mix(in srgb, var(--color-primary) 32%, transparent);
  background: var(--color-primary-soft);
  color: var(--color-primary);
  font-family: var(--font-heading);
  font-size: var(--text-xs);
  letter-spacing: .1em;
  line-height: 1.4;
  text-decoration: none;
  white-space: nowrap;
  transition: background-color .16s ease, color .16s ease, border-color .16s ease;
}

.pill:hover,
.pill:focus-visible {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
  text-decoration: none;
}

.pill--accent {
  background: var(--color-highlight);
  color: var(--color-accent);
  border-color: color-mix(in srgb, var(--color-accent) 34%, transparent);
}

.pill--accent:hover,
.pill--accent:focus-visible {
  background: var(--color-accent);
  color: var(--color-accent-ink);
  border-color: var(--color-accent);
}

.pill--quiet {
  background: var(--color-surface-deep);
  color: var(--color-ink-soft);
  border-color: var(--color-line);
  border-style: dashed;
}

.pill--quiet:hover,
.pill--quiet:focus-visible {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-pill);
  border: var(--border-thin) solid var(--color-primary);
  background: var(--color-primary-soft);
  color: var(--color-primary);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  letter-spacing: .06em;
  line-height: 1.4;
  text-decoration: none;
  box-shadow: inset 0 0 0 1px color-mix(in srgb, #ffffff 60%, transparent);
  transition: background-color .16s ease, color .16s ease, border-color .16s ease;
}

.btn:hover,
.btn:focus-visible {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
  text-decoration: none;
}

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

.btn--solid:hover,
.btn--solid:focus-visible {
  background: var(--color-accent);
  border-color: var(--color-accent);
  color: var(--color-accent-ink);
}

.btn--ghost {
  background: transparent;
  color: var(--color-ink);
  border-color: color-mix(in srgb, var(--color-ink) 30%, transparent);
}

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

/* ---------- breadcrumb ---------- */
.breadcrumb {
  padding: var(--space-3) 0 var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .12em;
  color: var(--color-ink-muted);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
}

.breadcrumb a {
  color: var(--color-ink-soft);
  text-decoration-color: var(--color-line);
}

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

.breadcrumb li[aria-current="page"] { color: var(--color-primary); }

.breadcrumb li + li::before {
  content: "/";
  margin-right: 6px;
  color: var(--color-line);
}

/* ---------- prose ---------- */
.prose {
  max-width: var(--measure);
  font-size: var(--text-base);
  color: var(--color-ink);
}

.prose p { margin: 0 0 var(--space-3); }
.prose h2 { font-size: var(--text-xl); margin: var(--space-6) 0 var(--space-2); }
.prose h3 { font-size: var(--text-lg); margin: var(--space-4) 0 var(--space-1); }
.prose ul,
.prose ol { margin: 0 0 var(--space-3) var(--space-3); list-style: disc; }
.prose li { margin-bottom: 6px; }
.prose strong { font-weight: var(--weight-heading); color: var(--color-primary); }

.section--contrast .prose p,
.section--contrast .prose li { color: color-mix(in srgb, var(--color-contrast-ink) 88%, transparent); }

/* ---------- panels ---------- */
.panel {
  position: relative;
  background: var(--color-surface-alt);
  border: var(--border-thin) solid var(--color-line);
  border-radius: 0;
  padding: var(--space-3);
  box-shadow: inset 0 1px 0 color-mix(in srgb, #ffffff 72%, transparent);
  transition: border-color .18s ease, background-color .18s ease;
}

.panel:hover { border-color: var(--color-primary); }

.panel--deep { background: var(--color-surface-deep); }

.panel--flat {
  background: transparent;
  border-color: var(--color-line);
  border-style: dashed;
}

.panel__head {
  display: flex;
  align-items: baseline;
  gap: var(--space-2);
  padding-bottom: var(--space-1);
  margin-bottom: var(--space-2);
  border-bottom: var(--border-thin) dotted var(--color-line);
}

.panel__title { font-size: var(--text-lg); }
.panel__meta {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .12em;
  color: var(--color-ink-muted);
}

/* ---------- index tag ---------- */
.index-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px var(--space-2);
  border-radius: var(--radius-pill);
  border: var(--border-thin) dashed var(--color-line);
  background: var(--color-surface-deep);
  color: var(--color-ink-soft);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .14em;
  line-height: 1.4;
  white-space: nowrap;
}

.index-tag--primary {
  background: var(--color-primary-soft);
  color: var(--color-primary);
  border-style: solid;
  border-color: color-mix(in srgb, var(--color-primary) 36%, transparent);
}

.index-tag--accent {
  background: var(--color-highlight);
  color: var(--color-accent);
  border-style: solid;
  border-color: color-mix(in srgb, var(--color-accent) 36%, transparent);
}

.index-tag--float { margin: calc(var(--space-2) * -1) 0 0 calc(var(--space-2) * -1); }

/* ---------- ledger ---------- */
.ledger {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-sm);
}

.ledger caption {
  text-align: left;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .16em;
  color: var(--color-ink-muted);
  padding-bottom: var(--space-1);
}

.ledger th {
  text-align: left;
  padding: var(--space-1) var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-body);
  letter-spacing: .14em;
  color: var(--color-ink-muted);
  background: var(--color-surface-deep);
  border-bottom: var(--border-thin) solid var(--color-line);
  white-space: nowrap;
}

.ledger td {
  padding: var(--space-1) var(--space-2);
  border-bottom: var(--border-thin) dotted var(--color-line);
  vertical-align: top;
}

.ledger tbody tr:hover td { background: var(--color-surface-alt); }

.ledger .num {
  font-family: var(--font-mono);
  letter-spacing: .06em;
  color: var(--color-primary);
  white-space: nowrap;
}

/* ---------- details entry ---------- */
.entry {
  border-bottom: var(--border-thin) dotted var(--color-line);
}

.entry > summary {
  display: flex;
  align-items: baseline;
  gap: var(--space-2);
  padding: var(--space-2) 0;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-heading);
  font-size: var(--text-base);
  color: var(--color-ink);
}

.entry > summary::-webkit-details-marker { display: none; }

.entry > summary::before {
  content: "+";
  flex: none;
  width: 1em;
  font-family: var(--font-mono);
  color: var(--color-primary);
}

.entry[open] > summary::before { content: "−"; }

.entry > summary:hover { color: var(--color-primary); }

.entry__body {
  padding: 0 0 var(--space-3) var(--space-4);
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
}

.entry__id {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .12em;
  color: var(--color-ink-muted);
}

/* ---------- copy button ---------- */
.copy-id {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px var(--space-2);
  border-radius: var(--radius-pill);
  border: var(--border-thin) dashed var(--color-line);
  background: var(--color-surface-alt);
  color: var(--color-ink-soft);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .12em;
  cursor: pointer;
  transition: background-color .16s ease, color .16s ease, border-color .16s ease;
}

.copy-id:hover,
.copy-id:focus-visible {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.copy-id[data-copied="ok"] {
  background: var(--color-primary);
  border-color: var(--color-primary);
  border-style: solid;
  color: var(--color-primary-ink);
}

.copy-id[data-copied="fail"] {
  background: var(--color-highlight);
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ---------- figures ---------- */
.figure {
  position: relative;
  margin: 0;
  background: var(--color-surface-deep);
  border: var(--border-thin) solid var(--color-line);
  border-radius: 0;
  overflow: hidden;
}

.figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 0;
}

.figure--wide img { aspect-ratio: 16 / 9; }
.figure--tall img { aspect-ratio: 3 / 4; }
.figure--square img { aspect-ratio: 1 / 1; }
.figure--strip img { aspect-ratio: 21 / 9; }

.figure__cap {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-2);
  justify-content: space-between;
  padding: 6px var(--space-2);
  background: var(--color-surface-alt);
  border-top: var(--border-thin) dotted var(--color-line);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .1em;
  color: var(--color-ink-muted);
}

.figure--overlay::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
  pointer-events: none;
}

.figure__overlay-text {
  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-lg);
  line-height: var(--leading-heading);
}

.img-ph {
  background:
    repeating-linear-gradient(135deg, transparent 0 9px, color-mix(in srgb, var(--color-primary) 10%, transparent) 9px 10px),
    linear-gradient(140deg, var(--color-surface-deep) 0%, var(--color-primary-soft) 100%);
}

/* ---------- misc ---------- */
.mono { font-family: var(--font-mono); letter-spacing: .1em; }
.small-caps-zh {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .2em;
  color: var(--color-ink-muted);
}
.page-title {
  font-size: var(--text-3xl);
  margin-bottom: var(--space-2);
}
.stack > * + * { margin-top: var(--space-2); }
.cluster { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-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;
}

/* ---------- footer ---------- */
.site-footer {
  margin-top: var(--section-y-lg);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-top: var(--border-thin) solid var(--color-contrast-line);
  overflow: hidden;
}

.site-footer__inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-8) var(--space-3) var(--space-4);
}

.site-footer__grid {
  display: grid;
  grid-template-columns: 2fr 2fr 1.2fr;
  gap: var(--space-6);
}

.site-footer__label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-body);
  letter-spacing: .24em;
  text-transform: uppercase;
  color: var(--color-contrast-accent);
  padding-bottom: var(--space-1);
  margin-bottom: var(--space-2);
  border-bottom: var(--border-thin) dotted var(--color-contrast-line);
}

.sitemap {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 6px var(--space-3);
}

.sitemap a {
  display: inline-block;
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
  text-decoration-color: var(--color-contrast-line);
}

.sitemap a:hover,
.sitemap a:focus-visible {
  color: var(--color-primary-soft);
  text-decoration-color: var(--color-contrast-accent);
}

.contact-list {
  display: grid;
  gap: 6px;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: .04em;
}

.contact-list li {
  display: flex;
  gap: var(--space-1);
  align-items: baseline;
}

.contact-list__key {
  flex: none;
  width: 3em;
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
  font-size: var(--text-xs);
  letter-spacing: .16em;
}

.contact-list__val { color: var(--color-contrast-ink); }

.site-footer__note {
  margin: var(--space-2) 0 0;
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 74%, transparent);
  max-width: 40ch;
}

.site-footer__col--action { display: grid; gap: var(--space-1); align-content: start; }

.site-footer .btn--ghost {
  color: var(--color-contrast-ink);
  border-color: var(--color-contrast-line);
  background: transparent;
}

.site-footer .btn--ghost:hover,
.site-footer .btn--ghost:focus-visible {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-ink);
}

.site-footer .btn--solid {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-primary-ink);
}

.site-footer .btn--solid:hover,
.site-footer .btn--solid:focus-visible {
  background: var(--color-contrast-accent);
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

.site-footer__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-4);
  justify-content: space-between;
  margin-top: var(--space-6);
  padding-top: var(--space-3);
  border-top: var(--border-thin) dashed var(--color-contrast-line);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: .12em;
  color: color-mix(in srgb, var(--color-contrast-ink) 76%, transparent);
}

.site-footer__logotype {
  margin-top: var(--space-4);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  font-size: clamp(44px, 11.5vw, 150px);
  line-height: .86;
  letter-spacing: -.02em;
  white-space: nowrap;
  color: var(--color-contrast-surface);
  color: color-mix(in srgb, var(--color-contrast-ink) 15%, var(--color-contrast-surface));
  user-select: none;
}

/* ---------- responsive ---------- */
@media (max-width: 1180px) {
  .statusbar--header { display: none; }
}

@media (max-width: 960px) {
  .nav-toggle { display: inline-flex; }

  .site-nav {
    position: absolute;
    top: calc(100% + 1px);
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-2);
    margin-left: 0;
    padding: var(--space-3);
    background: var(--color-surface);
    color: var(--color-ink);
    border: var(--border-thin) solid var(--color-line);
    border-top: 2px dotted var(--color-primary);
    box-shadow: inset 0 -1px 0 color-mix(in srgb, #ffffff 60%, transparent);
  }

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

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 6px;
  }

  .site-nav__link {
    display: block;
    padding: var(--space-1) var(--space-2);
    font-size: var(--text-base);
  }

  .site-nav .statusbar--header {
    display: inline-flex;
    align-self: flex-start;
    color: var(--color-ink-soft);
    border-color: var(--color-line);
  }

  .site-footer__grid { grid-template-columns: 1fr 1fr; }
  .site-footer__col--action { grid-column: 1 / -1; }
  .site-footer__note { max-width: 60ch; }
}

@media (max-width: 720px) {
  .site-header__inner { padding: var(--space-1) var(--space-2); }
  .brand__sub { display: none; }
  .site-nav { left: calc(var(--space-2) * -1); right: calc(var(--space-2) * -1); }

  .section { padding: var(--space-6) 0; }
  .section--lg { padding: var(--space-8) 0; }
  .page-title { font-size: var(--text-2xl); }
  .section__title { font-size: var(--text-xl); }

  .grid--12,
  .grid--split { grid-template-columns: repeat(4, minmax(0, 1fr)); }

  .site-footer__inner { padding: var(--space-6) var(--space-2) var(--space-3); }
  .site-footer__grid { grid-template-columns: 1fr; gap: var(--space-4); }
  .sitemap { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .site-footer__meta { flex-direction: column; gap: var(--space-1); }
  .site-footer__logotype { white-space: normal; }
  .ledger th,
  .ledger td { padding: 6px var(--space-1); }
}

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

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

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

  .skip-link { transition: none; }
}