:root {
  --color-surface: #f8f7f7;
  --color-surface-alt: #eeeded;
  --color-surface-deep: #e1dfdf;
  --color-ink: #382e33;
  --color-ink-soft: #695962;
  --color-ink-muted: #86747e;
  --color-line: #d5d3d4;
  --color-primary: #bc4385;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #f0dee7;
  --color-accent: #10893c;
  --color-accent-ink: #ffffff;
  --color-highlight: #cee3d5;
  --color-focus: #088234;
  --color-contrast-surface: #261820;
  --color-contrast-ink: #e7e4e6;
  --color-contrast-line: #50454c;
  --color-contrast-accent: #1be464;
  --overlay-scrim: linear-gradient(180deg, rgba(38, 24, 32, 0.35) 0%, rgba(38, 24, 32, 0.72) 55%, rgba(38, 24, 32, 0.92) 100%);
  --font-heading: "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", 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(38px, 7.9vw, 101px);
  --text-figure: clamp(32px, 5.7vw, 73px);
  --weight-heading: 602;
  --weight-body: 400;
  --leading-body: 1.69;
  --leading-heading: 1.26;
  --tracking-heading: 0.005em;
  --radius-sm: 0px;
  --radius-md: 0px;
  --radius-lg: 1px;
  --radius-pill: 1px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: none;
  --shadow-2: none;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1220px;
  --measure: 68ch;
  --gutter: 32px;
  --section-y: 83px;
  --section-y-lg: 116px;
}

/* ============ reset ============ */
*, *::before, *::after { box-sizing: border-box; }
html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
  scroll-padding-top: 104px;
}
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);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}
img, svg, video { display: block; max-width: 100%; height: auto; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
ul, ol { margin: 0; padding: 0; list-style: none; }
h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd { margin: 0; }
a { color: inherit; text-decoration: none; }
table { border-collapse: collapse; }
:focus-visible { outline: 2px solid var(--color-focus); outline-offset: 3px; }
::selection { background-color: var(--color-primary-soft); color: var(--color-ink); }

/* ============ typography ============ */
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);
}
h1 { font-size: var(--text-3xl); }
h2 { font-size: var(--text-2xl); }
h3 { font-size: var(--text-lg); font-weight: 600; }
h4 { font-size: var(--text-base); font-weight: 600; }
p { line-height: var(--leading-body); }
.display {
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: 700;
  line-height: 1.02;
  letter-spacing: -0.012em;
}
.figure-xl {
  font-family: var(--font-heading);
  font-size: var(--text-figure);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.01em;
}
.mono-label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
  text-transform: uppercase;
}
.section-eyebrow {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
  margin-bottom: var(--space-3);
}
.section-eyebrow::after {
  content: "";
  flex: 1;
  height: var(--border-thin);
  background-color: var(--color-line);
}
.mark-underline {
  border-bottom: 2px solid var(--color-primary);
  padding-bottom: 1px;
}
.mark-highlight {
  background-color: var(--color-highlight);
  color: var(--color-ink);
  padding: 0 4px;
}
.lede { font-size: var(--text-lg); color: var(--color-ink-soft); }
.muted { color: var(--color-ink-soft); }
.mono-meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}

/* ============ layout ============ */
.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--space-4);
}
.section { padding: var(--section-y) 0; }
.section--lg { padding: var(--section-y-lg) 0; }
.section--tight { padding: var(--space-6) 0; }
.section--alt { background-color: var(--color-surface-alt); }
.section--deep { background-color: var(--color-surface-deep); }
.section--contrast {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.section--line { border-top: var(--border-thin) solid var(--color-line); }

.prose { max-width: var(--measure); }
.prose p { color: var(--color-ink-soft); }
.prose p + p { margin-top: var(--space-2); }
.prose h2, .prose h3 { margin-top: var(--space-6); margin-bottom: var(--space-2); }
.prose ul, .prose ol { margin-top: var(--space-2); }
.prose li {
  position: relative;
  padding-left: var(--space-4);
  color: var(--color-ink-soft);
}
.prose li + li { margin-top: var(--space-1); }
.prose li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--color-primary);
  font-family: var(--font-mono);
}

.grid { display: grid; gap: var(--gutter); }
.grid-12 { display: grid; grid-template-columns: repeat(12, 1fr); gap: var(--gutter); }
.grid-auto { display: grid; gap: var(--gutter); grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); }
.span-1 { grid-column: span 1; }
.span-2 { grid-column: span 2; }
.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-5 { grid-column: span 5; }
.span-6 { grid-column: span 6; }
.span-7 { grid-column: span 7; }
.span-8 { grid-column: span 8; }
.span-9 { grid-column: span 9; }
.span-10 { grid-column: span 10; }
.span-11 { grid-column: span 11; }
.span-12 { grid-column: span 12; }

/* ---- split screen core ---- */
.split {
  display: grid;
  grid-template-columns: 7fr 5fr;
  align-items: stretch;
}
.split--reverse { grid-template-columns: 5fr 7fr; }
.split--even { grid-template-columns: 1fr 1fr; }
.split__pane { padding: var(--section-y-lg) clamp(var(--space-3), 4vw, var(--space-8)); }
.split__pane--narrative { background-color: var(--color-surface); color: var(--color-ink); }
.split__pane--quiet { background-color: var(--color-surface-alt); color: var(--color-ink); }
.split__pane--index {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.split__pane--index .mono-label,
.split__pane--index .mono-meta { color: color-mix(in srgb, var(--color-contrast-ink) 62%, var(--color-contrast-surface)); }
.split__pane--index .lede { color: color-mix(in srgb, var(--color-contrast-ink) 80%, var(--color-contrast-surface)); }

/* ---- dark context ---- */
.theme-dark {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-color: var(--color-contrast-line);
}
.theme-dark .mono-label,
.theme-dark .mono-meta { color: color-mix(in srgb, var(--color-contrast-ink) 62%, var(--color-contrast-surface)); }
.theme-dark .section-eyebrow { color: color-mix(in srgb, var(--color-contrast-ink) 70%, var(--color-contrast-surface)); }
.theme-dark .section-eyebrow::after { background-color: var(--color-contrast-line); }
.theme-dark .prose p,
.theme-dark .prose li,
.theme-dark .lede { color: color-mix(in srgb, var(--color-contrast-ink) 82%, var(--color-contrast-surface)); }
.theme-dark .mark-highlight { background-color: color-mix(in srgb, var(--color-contrast-accent) 26%, var(--color-contrast-surface)); color: var(--color-contrast-ink); }

/* ============ skip link + reading progress ============ */
.skip-link {
  position: absolute;
  left: var(--space-2);
  top: -72px;
  z-index: 90;
  padding: var(--space-1) var(--space-2);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  border: var(--border-thin) solid var(--color-contrast-accent);
  transition: top 160ms ease;
}
.skip-link:focus { top: var(--space-2); }

.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  z-index: 80;
  background-color: transparent;
  pointer-events: none;
}
.reading-progress__bar {
  display: block;
  width: 0;
  height: 100%;
  background-color: var(--color-contrast-accent);
}

/* ============ header ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background-color: var(--color-surface);
  border-bottom: var(--border-thin) solid var(--color-line);
}
.header-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-3) var(--space-4);
  display: grid;
  grid-template-columns: 3fr 9fr;
  gap: var(--gutter);
  align-items: stretch;
}
.brand-block { display: flex; flex-direction: column; gap: var(--space-1); }
.brand-link { display: inline-flex; align-items: center; gap: var(--space-1); }
.brand-mark {
  width: 14px;
  height: 14px;
  background-color: var(--color-primary);
  flex: none;
}
.brand-line {
  font-family: var(--font-heading);
  font-size: var(--text-xl);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: 0.02em;
}
.brand-descriptor {
  font-size: var(--text-xs);
  color: var(--color-ink-soft);
  line-height: 1.5;
}
.header-utility {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1) var(--space-2);
  margin-top: var(--space-1);
}
.header-utility__item {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}
.header-utility__item + .header-utility__item { border-left: var(--border-thin) solid var(--color-line); padding-left: var(--space-2); }

.header-nav-zone {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  border-left: var(--border-thin) solid var(--color-line);
  padding-left: var(--space-4);
}
.site-nav { flex: 1 1 auto; }
.nav-list { display: flex; flex-wrap: wrap; gap: var(--space-1) var(--space-3); }
.nav-link {
  display: inline-block;
  padding: var(--space-1) 0;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  color: var(--color-ink-soft);
  border-bottom: 2px solid transparent;
  transition: color 180ms ease, border-color 180ms ease;
}
.nav-link:hover { color: var(--color-ink); border-bottom-color: var(--color-primary-soft); }
.nav-link[aria-current="page"] {
  color: var(--color-ink);
  border-bottom-color: var(--color-primary);
}
.header-cta { flex: none; }

.nav-toggle {
  display: none;
  align-items: center;
  gap: 6px;
  padding: var(--space-1) var(--space-2);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
}
.nav-toggle__bar {
  display: block;
  width: 14px;
  height: 2px;
  background-color: var(--color-contrast-accent);
}
.nav-toggle__label {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
}
.nav-toggle[aria-expanded="true"] { border-color: var(--color-contrast-accent); }

.header-rule { height: var(--border-thin); background-color: var(--color-line); }
.header-rule__seg { display: block; height: 100%; width: 25%; background-color: var(--color-primary); }

/* ============ footer ============ */
.site-footer {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-top: var(--border-thin) solid var(--color-contrast-line);
}
.footer-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--section-y) var(--space-4) var(--space-6);
  display: grid;
  grid-template-columns: 5fr 7fr;
  gap: var(--gutter);
}
.footer-brand { display: flex; flex-direction: column; gap: var(--space-2); }
.footer-brand__line {
  font-family: var(--font-heading);
  font-size: var(--text-2xl);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: 0.02em;
}
.footer-brand__descriptor {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-contrast-accent);
}
.footer-brand__closing {
  max-width: 34ch;
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 76%, var(--color-contrast-surface));
}
.footer-cols {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-3);
  border-left: var(--border-thin) solid var(--color-contrast-line);
  padding-left: var(--space-4);
}
.footer-col__title {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 400;
  letter-spacing: 0.04em;
  color: var(--color-contrast-accent);
  padding-bottom: var(--space-1);
  margin-bottom: var(--space-2);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}
.footer-list li + li { margin-top: 6px; }
.footer-link {
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
  border-bottom: 1px solid transparent;
  transition: color 180ms ease, border-color 180ms ease;
}
.footer-link:hover { border-bottom-color: var(--color-contrast-accent); }
.footer-meta {
  max-width: var(--container);
  margin: 0 auto;
  padding: var(--space-3) var(--space-4) var(--space-6);
  border-top: var(--border-thin) solid var(--color-contrast-line);
  display: grid;
  grid-template-columns: 7fr 5fr;
  gap: var(--gutter);
  align-items: start;
}
.footer-contact {
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 82%, var(--color-contrast-surface));
}
.footer-legal {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, var(--color-contrast-surface));
  text-align: right;
}

/* ============ buttons ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-3);
  border: var(--border-thin) solid var(--color-primary);
  border-radius: var(--radius-sm);
  background-color: transparent;
  color: var(--color-primary);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  line-height: 1.2;
  transition: background-color 180ms ease, color 180ms ease, border-color 180ms ease;
}
.btn:hover {
  background-color: var(--color-primary-soft);
  color: var(--color-ink);
}
.btn--primary {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-primary);
}
.btn--primary:hover {
  background-color: color-mix(in srgb, var(--color-primary) 82%, var(--color-contrast-surface));
  color: var(--color-primary-ink);
}
.btn--contrast {
  border-color: var(--color-contrast-accent);
  color: var(--color-contrast-accent);
}
.btn--contrast:hover {
  background-color: color-mix(in srgb, var(--color-contrast-accent) 18%, var(--color-contrast-surface));
  color: var(--color-contrast-ink);
}
.btn--block { display: flex; width: 100%; }

.copy-btn {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  padding: 2px var(--space-1);
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-sm);
  color: var(--color-ink-muted);
  background-color: transparent;
  transition: border-color 160ms ease, color 160ms ease;
}
.copy-btn:hover { border-color: var(--color-primary); color: var(--color-primary); }
.copy-btn[data-copied="true"] { border-color: var(--color-accent); color: var(--color-accent); }

/* ============ tags ============ */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px var(--space-1);
  background-color: var(--color-primary-soft);
  color: var(--color-ink);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
}
.tag--accent { background-color: var(--color-highlight); }
.tag--line {
  background-color: transparent;
  border-color: var(--color-line);
  color: var(--color-ink-muted);
}
.theme-dark .tag,
.split__pane--index .tag {
  background-color: color-mix(in srgb, var(--color-contrast-accent) 16%, var(--color-contrast-surface));
  color: var(--color-contrast-ink);
}

/* ============ entries ============ */
.entry {
  display: grid;
  grid-template-columns: 68px 1fr;
  gap: var(--space-2) var(--space-3);
  padding: var(--space-3) 0;
  border-top: var(--border-thin) solid var(--color-line);
}
.entry__num {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  color: var(--color-primary);
}
.entry__title {
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: 600;
  line-height: 1.32;
}
.entry__meta {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
  margin-top: 4px;
}
.entry__body {
  grid-column: 2;
  max-width: var(--measure);
  color: var(--color-ink-soft);
  font-size: var(--text-sm);
}
.entry--accent .entry__num { color: var(--color-accent); }
.theme-dark .entry,
.split__pane--index .entry { border-top-color: var(--color-contrast-line); }
.theme-dark .entry__num,
.split__pane--index .entry__num { color: var(--color-contrast-accent); }
.theme-dark .entry__title,
.split__pane--index .entry__title { color: var(--color-contrast-ink); }
.theme-dark .entry__meta,
.split__pane--index .entry__meta { color: color-mix(in srgb, var(--color-contrast-ink) 60%, var(--color-contrast-surface)); }
.theme-dark .entry__body,
.split__pane--index .entry__body { color: color-mix(in srgb, var(--color-contrast-ink) 80%, var(--color-contrast-surface)); }

/* ============ figure / image containers ============ */
.figure {
  background-color: var(--color-surface-deep);
  border: var(--border-thin) solid var(--color-line);
  padding: var(--space-1);
}
.figure__frame {
  position: relative;
  overflow: hidden;
  background-color: var(--color-surface-alt);
  aspect-ratio: 4 / 3;
}
.figure__frame > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.figure__scrim {
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
}
.figure__caption {
  display: block;
  padding: var(--space-1) 2px 2px;
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}
.figure--tall .figure__frame { aspect-ratio: 3 / 4; }
.figure--wide .figure__frame { aspect-ratio: 16 / 9; }
.figure--square .figure__frame { aspect-ratio: 1 / 1; }
.theme-dark .figure,
.split__pane--index .figure {
  background-color: var(--color-contrast-surface);
  border-color: var(--color-contrast-line);
}
.theme-dark .figure__caption,
.split__pane--index .figure__caption { color: color-mix(in srgb, var(--color-contrast-ink) 66%, var(--color-contrast-surface)); }

/* ============ breadcrumbs ============ */
.breadcrumbs {
  padding: var(--space-2) 0;
  border-bottom: var(--border-thin) solid var(--color-line);
}
.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  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);
}
.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 { border-bottom: 1px solid transparent; }
.breadcrumb-list a:hover { border-bottom-color: var(--color-primary); color: var(--color-ink); }

/* ============ tables ============ */
.table-scroll { overflow-x: auto; border: var(--border-thin) solid var(--color-line); }
.doc-table {
  width: 100%;
  min-width: 560px;
  font-size: var(--text-sm);
}
.doc-table thead th {
  background-color: var(--color-surface-deep);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 400;
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
  text-align: left;
}
.doc-table th,
.doc-table td {
  padding: var(--space-2);
  border-bottom: var(--border-thin) solid var(--color-line);
  vertical-align: top;
}
.doc-table tbody tr:last-child th,
.doc-table tbody tr:last-child td { border-bottom: 0; }

/* ============ inline link ============ */
.link-underline {
  color: var(--color-ink);
  border-bottom: 1px solid var(--color-primary);
  padding-bottom: 1px;
  transition: border-color 160ms ease;
}
.link-underline:hover { border-bottom-width: 2px; }
.theme-dark .link-underline,
.split__pane--index .link-underline {
  color: var(--color-contrast-ink);
  border-bottom-color: var(--color-contrast-accent);
}

/* ============ scroll spy / reveal ============ */
[data-spy-link].is-current {
  color: var(--color-ink);
  border-bottom-color: var(--color-primary);
}
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 320ms ease, transform 320ms ease;
}
html.js [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ============ responsive ============ */
@media (max-width: 1100px) {
  .header-inner { grid-template-columns: 4fr 8fr; }
  .footer-inner { grid-template-columns: 1fr; }
  .footer-cols { border-left: 0; border-top: var(--border-thin) solid var(--color-contrast-line); padding-left: 0; padding-top: var(--space-4); }
}
@media (max-width: 900px) {
  .header-inner {
    grid-template-columns: 1fr;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-3);
  }
  .brand-block {
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: baseline;
    gap: var(--space-1) var(--space-2);
  }
  .brand-link { grid-column: 1; }
  .brand-descriptor { grid-column: 1 / -1; }
  .header-utility { display: none; }
  .header-nav-zone {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: var(--space-2);
    align-items: center;
    border-left: 0;
    border-top: var(--border-thin) solid var(--color-line);
    padding-left: 0;
    padding-top: var(--space-2);
  }
  .nav-toggle { display: inline-flex; grid-column: 1; justify-self: start; }
  .header-cta { grid-column: 2; justify-self: end; }
  .site-nav {
    grid-column: 1 / -1;
    display: none;
    border-top: var(--border-thin) solid var(--color-line);
    margin-top: var(--space-1);
    padding-top: var(--space-1);
  }
  .site-header[data-open="true"] .site-nav { display: block; }
  .nav-list { flex-direction: column; gap: 0; }
  .nav-item + .nav-item { border-top: var(--border-thin) solid var(--color-line); }
  .nav-link {
    display: block;
    padding: var(--space-2) 0;
    border-bottom: 0;
    border-left: 2px solid transparent;
    padding-left: var(--space-2);
  }
  .nav-link[aria-current="page"] {
    border-bottom-color: transparent;
    border-left-color: var(--color-primary);
    background-color: var(--color-primary-soft);
  }

  .grid-12 { grid-template-columns: repeat(6, 1fr); }
  .span-1, .span-2 { grid-column: span 2; }
  .span-3, .span-4 { grid-column: span 3; }
  .span-5, .span-6,
  .span-7, .span-8,
  .span-9, .span-10,
  .span-11, .span-12 { grid-column: span 6; }

  .split,
  .split--reverse,
  .split--even { grid-template-columns: 1fr; }
  .split__pane { padding: var(--section-y) var(--space-4); }

  .footer-cols { grid-template-columns: repeat(2, 1fr); }
  .footer-meta { grid-template-columns: 1fr; padding-bottom: var(--space-6); }
  .footer-legal { text-align: left; }
  .footer-brand__closing { max-width: none; }
}
@media (max-width: 600px) {
  .container { padding: 0 var(--space-3); }
  .section { padding: var(--space-6) 0; }
  .section--lg { padding: var(--section-y) 0; }
  .grid-12 { grid-template-columns: 1fr; }
  .span-1, .span-2, .span-3, .span-4, .span-5, .span-6,
  .span-7, .span-8, .span-9, .span-10, .span-11, .span-12 { grid-column: span 1; }
  .footer-cols { grid-template-columns: 1fr; }
  .entry { grid-template-columns: 1fr; }
  .entry__body { grid-column: 1; }
  .brand-line { font-size: var(--text-lg); }
  .display { font-size: var(--text-4xl); }
}

/* ============ motion preferences ============ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
  html.js [data-reveal] { opacity: 1; transform: none; }
  .skip-link { transition: none; }
  .reading-progress__bar { transition: none; }
}

@media print {
  .site-header, .reading-progress, .skip-link { display: none; }
  .site-footer { background: none; color: var(--color-ink); }
}