:root {
  --color-surface: #0e0e0e;
  --color-surface-alt: #1f1f1f;
  --color-surface-deep: #333534;
  --color-ink: #c8d0cc;
  --color-ink-soft: #84958c;
  --color-ink-muted: #77887f;
  --color-line: #2f3130;
  --color-primary: #26d97f;
  --color-primary-ink: #111814;
  --color-primary-soft: #112a1e;
  --color-accent: #1be47e;
  --color-accent-ink: #111814;
  --color-highlight: #103522;
  --color-focus: #0ef17e;
  --color-contrast-surface: #f5f6f6;
  --color-contrast-ink: #333836;
  --color-contrast-line: #cacccc;
  --color-contrast-accent: #0f8047;
  --overlay-scrim: linear-gradient(180deg, rgba(245, 246, 246, 0.35) 0%, rgba(245, 246, 246, 0.72) 55%, rgba(245, 246, 246, 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: 11.4px;
  --text-sm: 14.3px;
  --text-base: 16px;
  --text-lg: 20.0px;
  --text-xl: 25.0px;
  --text-2xl: 31.2px;
  --text-3xl: 39.1px;
  --text-4xl: 48.8px;
  --text-display: clamp(40px, 8.2vw, 105px);
  --text-figure: clamp(33px, 5.9vw, 76px);
  --weight-heading: 621;
  --weight-body: 400;
  --leading-body: 1.67;
  --leading-heading: 1.22;
  --tracking-heading: 0.021em;
  --radius-sm: 2px;
  --radius-md: 4px;
  --radius-lg: 6px;
  --radius-pill: 6px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: none;
  --shadow-2: none;
  --space-1: 6px;
  --space-2: 12px;
  --space-3: 18px;
  --space-4: 24px;
  --space-6: 36px;
  --space-8: 48px;
  --container: 1320px;
  --measure: 71ch;
  --gutter: 24px;
  --section-y: 60px;
  --section-y-lg: 84px;
}

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

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: var(--space-8);
}

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

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

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

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

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

/* ============ base ============ */
body {
  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);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

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

h1 { font-size: var(--text-3xl); }
h2 { font-size: var(--text-2xl); }
h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }
h5, h6 { font-size: var(--text-base); }

p { max-width: var(--measure); }

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

strong { color: var(--color-ink); font-weight: var(--weight-heading); }

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

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

/* ============ utilities ============ */
.shell {
  width: min(100% - (var(--gutter) * 2), var(--container));
  margin-inline: auto;
}

.mono,
.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

.skip-link {
  position: fixed;
  top: -200px;
  left: var(--gutter);
  z-index: 200;
  display: inline-flex;
  align-items: center;
  padding: var(--space-2) var(--space-4);
  background-color: var(--color-accent);
  color: var(--color-accent-ink);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  border-radius: var(--radius-md);
  transition: top 150ms ease-out;
}

.skip-link:focus {
  top: var(--space-2);
}

/* ============ header ============ */
.site-header {
  position: relative;
  z-index: 60;
  background-color: var(--color-surface);
  border-bottom: var(--border-thin) dotted var(--color-line);
}

.header-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4) var(--space-6);
  padding-block: var(--space-4);
}

.brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  min-width: 0;
}

.brand-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}

.brand-mark {
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}

.brand-mark::after {
  content: "";
  display: block;
  width: 8px;
  height: 8px;
  background-color: var(--color-primary);
  border-radius: var(--radius-sm);
}

.brand-link:hover .brand-mark,
.brand-link:hover .brand-mark::after {
  color: var(--color-accent);
  background-color: var(--color-accent);
}

.brand-tagline {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: var(--color-ink-soft);
  max-width: none;
}

.brand-status {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
  max-width: none;
}

.status-dot {
  display: inline-block;
  flex: none;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--color-primary);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: var(--color-ink);
  border: var(--border-thin) dotted var(--color-line);
  border-radius: var(--radius-md);
  background-color: var(--color-surface-alt);
  transition: color 150ms ease-out, border-color 150ms ease-out;
}

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

.nav-toggle[data-open] {
  color: var(--color-accent-ink);
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  border-style: solid;
}

.nav-toggle-bars {
  display: grid;
  gap: 3px;
  width: 14px;
}

.nav-toggle-bars::before,
.nav-toggle-bars::after {
  content: "";
  display: block;
  height: 1px;
  background-color: currentColor;
}

.site-nav {
  display: flex;
  align-items: flex-start;
  gap: var(--space-6);
  padding-top: var(--space-1);
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-4);
}

.nav-item { min-width: 0; }

.nav-link {
  position: relative;
  display: inline-flex;
  align-items: baseline;
  gap: var(--space-1);
  padding-block: var(--space-1);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink-soft);
  border-bottom: var(--border-thin) dotted transparent;
  transition: color 150ms ease-out, border-color 150ms ease-out;
}

.nav-link:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

.nav-num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-xs);
  color: var(--color-ink-muted);
  padding: 0 3px;
  border-radius: var(--radius-sm);
  transition: background-color 150ms ease-out, color 150ms ease-out;
}

.nav-link:hover .nav-num { color: var(--color-primary); }

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

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

.nav-utility {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-3);
  padding-left: var(--space-4);
  border-left: var(--border-thin) dotted var(--color-line);
}

.util-link {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
  border-bottom: var(--border-thin) dotted var(--color-line);
  padding-bottom: 1px;
  transition: color 150ms ease-out, border-color 150ms ease-out;
}

.util-link:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

/* ============ footer ============ */
.site-footer {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-top: var(--border-thin) dotted var(--color-contrast-line);
}

.footer-inner { padding-block: var(--space-8) var(--space-6); }

.footer-grid {
  display: grid;
  grid-template-columns: 1.3fr repeat(3, 1fr);
  gap: var(--space-6) var(--gutter);
  padding-bottom: var(--space-6);
  border-bottom: var(--border-thin) dotted var(--color-contrast-line);
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  min-width: 0;
}

.footer-brand-mark {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
  max-width: none;
}

.footer-brand-tagline {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: color-mix(in srgb, var(--color-contrast-ink) 72%, transparent);
  max-width: none;
}

.site-footer .brand-status {
  color: color-mix(in srgb, var(--color-contrast-ink) 78%, transparent);
}

.site-footer .status-dot { background-color: var(--color-contrast-accent); }

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

.footer-col-title {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: var(--weight-heading);
  letter-spacing: 0.12em;
  color: var(--color-contrast-accent);
  padding-bottom: var(--space-2);
  border-bottom: var(--border-thin) dotted var(--color-contrast-line);
  margin-bottom: var(--space-3);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.footer-links a {
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
  border-bottom: var(--border-thin) dotted transparent;
  transition: color 150ms ease-out, border-color 150ms ease-out;
}

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

.footer-meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  color: color-mix(in srgb, var(--color-contrast-ink) 80%, transparent);
  word-break: break-all;
}

.footer-note {
  font-size: var(--text-xs);
  color: color-mix(in srgb, var(--color-contrast-ink) 76%, transparent);
  padding-top: var(--space-3);
  max-width: var(--measure);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-6);
  align-items: baseline;
  margin-top: var(--space-3);
  padding-top: var(--space-3);
  border-top: var(--border-thin) dotted var(--color-contrast-line);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: color-mix(in srgb, var(--color-contrast-ink) 74%, transparent);
}

.footer-legal-icp { color: var(--color-contrast-ink); }

/* ============ sections & grid ============ */
.section {
  background-color: var(--color-surface);
  padding-block: var(--section-y);
}

.section--alt { background-color: var(--color-surface-alt); }
.section--lg { padding-block: var(--section-y-lg); }
.section--tight { padding-block: var(--space-6); }

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

.section--contrast h1,
.section--contrast h2,
.section--contrast h3,
.section--contrast h4 { color: var(--color-contrast-ink); }

.section--contrast p,
.section--contrast li { color: var(--color-contrast-ink); }

.section--contrast a {
  color: var(--color-contrast-ink);
  border-bottom: var(--border-thin) dotted var(--color-contrast-line);
  transition: color 150ms ease-out, border-color 150ms ease-out;
}

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

.section--contrast .eyebrow { color: var(--color-contrast-accent); }
.section--contrast .eyebrow::before { background-color: var(--color-contrast-accent); }

.section-head {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  color: var(--color-primary);
}

.eyebrow::before {
  content: "";
  display: block;
  width: 18px;
  height: 1px;
  background-color: var(--color-primary);
}

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
}

.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-6 { grid-column: span 6; }
.span-8 { grid-column: span 8; }
.span-9 { grid-column: span 9; }
.span-12 { grid-column: span 12; }

/* ============ frame ============ */
.frame {
  position: relative;
  border: var(--border-thin) dotted var(--color-line);
  border-radius: var(--radius-lg);
  padding: var(--space-6);
  background-color: var(--color-surface);
}

.frame::before,
.frame::after {
  content: "";
  position: absolute;
  width: 12px;
  height: 12px;
  border-top: var(--border-thin) solid var(--color-primary);
  border-left: var(--border-thin) solid var(--color-primary);
}

.frame::before { top: -1px; left: -1px; }
.frame::after { bottom: -1px; right: -1px; transform: rotate(180deg); }

.section--contrast .frame {
  background-color: var(--color-contrast-surface);
  border-color: var(--color-contrast-line);
}

.section--contrast .frame::before,
.section--contrast .frame::after { border-color: var(--color-contrast-accent); }

/* ============ index rail ============ */
.index-rail {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding-right: var(--space-4);
  border-right: var(--border-thin) dotted var(--color-line);
}

.index-rail__title {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.12em;
  color: var(--color-ink-muted);
  max-width: none;
}

.index-rail__list {
  display: flex;
  flex-direction: column;
  gap: 1px;
}

.index-rail__link {
  display: flex;
  align-items: baseline;
  gap: var(--space-2);
  padding: var(--space-1) var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-variant-numeric: tabular-nums;
  color: var(--color-ink-soft);
  border-left: 3px solid transparent;
  border-radius: var(--radius-sm);
  transition: color 150ms ease-out, background-color 150ms ease-out, border-color 150ms ease-out;
}

.index-rail__link:hover {
  color: var(--color-accent);
  background-color: var(--color-surface-alt);
  border-left-color: var(--color-accent);
}

.index-rail__link[aria-current="true"] {
  color: var(--color-accent);
  background-color: var(--color-primary-soft);
  border-left-color: var(--color-primary);
}

/* ============ panel ============ */
.panel {
  background-color: var(--color-surface-deep);
  border: var(--border-thin) dotted var(--color-line);
  border-radius: var(--radius-md);
  padding: var(--space-4);
}

.panel > * + * { margin-top: var(--space-3); }

/* ============ rows ============ */
.row-list {
  border-top: var(--border-thin) dotted var(--color-line);
}

.row {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: var(--space-1) var(--space-4);
  padding: var(--space-3) var(--space-3) var(--space-3) var(--space-4);
  border-bottom: var(--border-thin) dotted var(--color-line);
  transition: background-color 150ms ease-out;
}

.row::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background-color: transparent;
  transition: background-color 150ms ease-out;
}

.row:hover,
.row:focus-within { background-color: var(--color-surface-alt); }

.row:hover::before,
.row:focus-within::before { background-color: var(--color-accent); }

.row__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-xs);
  color: var(--color-primary);
  min-width: 2.4em;
}

.row__main {
  flex: 1 1 16ch;
  min-width: 0;
}

.row__main a {
  border-bottom: var(--border-thin) dotted var(--color-line);
  transition: color 150ms ease-out, border-color 150ms ease-out;
}

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

.row__meta {
  display: inline-flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1) var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-variant-numeric: tabular-nums;
  color: var(--color-ink-muted);
}

/* ============ tags & marks ============ */
.tag {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 2px var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-primary);
  background-color: var(--color-primary-soft);
  border: var(--border-thin) dotted color-mix(in srgb, var(--color-primary) 42%, transparent);
  border-radius: var(--radius-pill);
}

.tag--muted {
  color: var(--color-ink-muted);
  background-color: var(--color-surface-alt);
  border-color: var(--color-line);
}

.mark {
  display: inline-block;
  padding: 2px var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-accent-ink);
  background-color: var(--color-accent);
  border-radius: var(--radius-sm);
}

.mark--muted {
  color: var(--color-ink-muted);
  background-color: var(--color-surface-deep);
}

.section--contrast .tag {
  color: var(--color-contrast-accent);
  background-color: color-mix(in srgb, var(--color-contrast-accent) 12%, transparent);
  border-color: color-mix(in srgb, var(--color-contrast-accent) 40%, transparent);
}

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

/* ============ figure band ============ */
.figure-band {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4) var(--space-8);
  align-items: flex-end;
  padding: var(--space-4) var(--space-6);
  background-color: var(--color-highlight);
  border-left: 3px solid var(--color-primary);
  border-radius: var(--radius-md);
}

.figure {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  min-width: 0;
}

.figure__value {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-figure);
  line-height: 1;
  letter-spacing: -0.01em;
  color: var(--color-primary);
}

.figure__label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-ink-soft);
}

/* ============ image frames ============ */
.img-frame {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-md);
  background-color: var(--color-surface-alt);
  min-height: 220px;
  isolation: isolate;
}

.img-frame img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.img-frame__scrim {
  position: absolute;
  inset: 0;
  background-image: var(--overlay-scrim);
  pointer-events: none;
  z-index: 1;
}

.img-frame__body {
  position: relative;
  z-index: 2;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  gap: var(--space-2);
  min-height: inherit;
  padding: var(--space-6);
  color: var(--color-contrast-ink);
}

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

.img-frame--wide { aspect-ratio: 21 / 9; min-height: 260px; }
.img-frame--band { aspect-ratio: 3 / 1; min-height: 180px; }
.img-frame--tall { aspect-ratio: 4 / 3; min-height: 300px; }

/* ============ breadcrumb ============ */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}

.breadcrumb a {
  color: var(--color-ink-soft);
  border-bottom: var(--border-thin) dotted var(--color-line);
  transition: color 150ms ease-out, border-color 150ms ease-out;
}

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

.breadcrumb__sep { color: var(--color-line); }

/* ============ buttons ============ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  font-family: var(--font-heading);
  font-size: var(--text-sm);
  letter-spacing: var(--tracking-heading);
  color: var(--color-primary);
  background-color: transparent;
  border: var(--border-thin) dotted var(--color-primary);
  border-radius: var(--radius-md);
  transition: background-color 150ms ease-out, color 150ms ease-out, border-color 150ms ease-out;
}

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

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

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

.btn--quiet {
  color: var(--color-ink-soft);
  border-color: var(--color-line);
}

.btn--quiet:hover {
  background-color: var(--color-surface-deep);
  color: var(--color-accent);
  border-color: var(--color-accent);
}

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

.section--contrast .btn:hover {
  background-color: var(--color-contrast-accent);
  color: var(--color-contrast-surface);
}

/* ============ prose ============ */
.prose {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  max-width: var(--measure);
  text-align: left;
}

.prose p { color: var(--color-ink); }

/* ============ filter bar ============ */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
  padding-block: var(--space-3);
  border-top: var(--border-thin) dotted var(--color-line);
  border-bottom: var(--border-thin) dotted var(--color-line);
}

.filter-btn {
  padding: var(--space-1) var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  color: var(--color-ink-soft);
  background-color: transparent;
  border: var(--border-thin) dotted var(--color-line);
  border-radius: var(--radius-pill);
  transition: color 150ms ease-out, background-color 150ms ease-out, border-color 150ms ease-out;
}

.filter-btn:hover {
  color: var(--color-accent);
  border-color: var(--color-accent);
}

.filter-btn.is-active,
.filter-btn[aria-pressed="true"] {
  color: var(--color-accent-ink);
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  border-style: solid;
}

.filter-count {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-variant-numeric: tabular-nums;
  color: var(--color-ink-muted);
}

[data-filter-item][hidden] { display: none !important; }

/* ============ responsive ============ */
@media (max-width: 1180px) {
  .nav-list { gap: var(--space-1) var(--space-3); }
  .nav-utility { padding-left: var(--space-3); }
}

@media (max-width: 1024px) {
  .nav-toggle { display: inline-flex; }

  .header-inner { align-items: center; }

  .brand { flex: 1 1 auto; }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    display: none;
    flex-direction: column;
    gap: var(--space-4);
    padding: var(--space-4) var(--gutter) var(--space-6);
    background-color: var(--color-surface-alt);
    border-top: var(--border-thin) dotted var(--color-line);
    border-bottom: var(--border-thin) dotted var(--color-line);
    max-height: calc(100vh - 120px);
    overflow-y: auto;
  }

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

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

  .nav-item { width: 100%; }

  .nav-link {
    display: flex;
    justify-content: flex-start;
    width: 100%;
    padding-block: var(--space-2);
    border-bottom: var(--border-thin) dotted var(--color-line);
    border-left: 3px solid transparent;
    padding-left: var(--space-2);
  }

  .nav-link:hover,
  .nav-link[aria-current="page"] { border-left-color: var(--color-accent); }

  .nav-utility {
    padding-left: 0;
    padding-top: var(--space-3);
    border-left: 0;
    border-top: var(--border-thin) dotted var(--color-line);
  }
}

@media (max-width: 980px) {
  .grid-12 { grid-template-columns: repeat(6, minmax(0, 1fr)); }

  .span-3,
  .span-4,
  .span-6,
  .span-8,
  .span-9 { grid-column: span 6; }

  .index-rail {
    border-right: 0;
    border-bottom: var(--border-thin) dotted var(--color-line);
    padding-right: 0;
    padding-bottom: var(--space-3);
  }

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

  .figure-band { gap: var(--space-4) var(--space-6); padding: var(--space-4); }
}

@media (max-width: 620px) {
  .grid-12 { grid-template-columns: 1fr; }

  .span-3,
  .span-4,
  .span-6,
  .span-8,
  .span-9,
  .span-12 { grid-column: span 1; }

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

  .footer-legal { flex-direction: column; gap: var(--space-1); }

  .frame { padding: var(--space-4); }

  .img-frame__body { padding: var(--space-4); }

  .row { padding-left: var(--space-3); }
}

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

  *,
  *::before,
  *::after {
    transition-duration: 0ms !important;
    animation-duration: 0ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
  }
}