:root {
  --ink: #17212b;
  --paper: #f7f4ee;
  --surface: #fffdf8;
  --line: #b9b0a4;
  --muted: #625f59;
  --blue: #164b78;
  --red: #9b332d;
  --violet: #553b73;
  --green: #3f6b50;
  --max: 70rem;
}
* { box-sizing: border-box; }
html { color-scheme: light; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.55;
}
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: .16em; }
a:hover { color: var(--blue); }
.skip-link {
  position: absolute;
  left: -9999px;
  top: .75rem;
  z-index: 4;
  padding: .5rem .75rem;
  background: var(--ink);
  color: white;
}
.skip-link:focus { left: .75rem; }
.site-header {
  border-bottom: 1px solid var(--ink);
  background: var(--surface);
}
.header-inner {
  width: min(var(--max), calc(100% - 2rem));
  margin: auto;
  padding: 1rem 0 .85rem;
  display: grid;
  gap: .75rem;
}
.brand {
  text-transform: uppercase;
  letter-spacing: .08em;
  font-size: .74rem;
  font-weight: 760;
  text-decoration: none;
}
.primary-nav {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  font-size: .82rem;
  letter-spacing: .04em;
  text-transform: uppercase;
}
.primary-nav a { text-decoration: none; }
.primary-nav a[aria-current="page"] { color: var(--red); font-weight: 760; }
main { width: min(var(--max), calc(100% - 2rem)); margin: 0 auto; }
.hero {
  padding: clamp(3.5rem, 9vw, 7rem) 0 3rem;
  border-bottom: 1px solid var(--line);
}
.eyebrow, .kicker {
  margin: 0 0 .8rem;
  color: var(--red);
  font-size: .75rem;
  letter-spacing: .11em;
  font-weight: 760;
  text-transform: uppercase;
}
h1, h2, h3 {
  font-family: ui-serif, Georgia, Cambria, "Times New Roman", serif;
  color: var(--ink);
  line-height: 1.04;
}
h1 {
  max-width: 15ch;
  font-size: clamp(2.5rem, 8vw, 5.7rem);
  font-weight: 530;
  letter-spacing: -.045em;
  margin: 0;
}
h2 { font-size: clamp(1.6rem, 4vw, 2.75rem); margin: 0 0 1rem; letter-spacing: -.025em; }
h3 { font-size: 1.18rem; margin: 0 0 .55rem; }
.deck {
  max-width: 49rem;
  margin: 1.4rem 0 0;
  font-family: ui-serif, Georgia, Cambria, "Times New Roman", serif;
  font-size: clamp(1.22rem, 2.5vw, 1.72rem);
  line-height: 1.35;
}
.summary {
  max-width: 50rem;
  margin: 1.4rem 0 0;
  color: var(--muted);
  font-size: 1.04rem;
}
.actions {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
  margin: 2rem 0 0;
}
.button {
  display: inline-block;
  padding: .65rem .85rem;
  color: white;
  background: var(--ink);
  border: 1px solid var(--ink);
  text-decoration: none;
  font-size: .78rem;
  font-weight: 760;
  letter-spacing: .06em;
  text-transform: uppercase;
}
.button.secondary { color: var(--ink); background: transparent; }
.section { padding: clamp(2.8rem, 7vw, 5.25rem) 0; border-bottom: 1px solid var(--line); }
.section > :last-child { margin-bottom: 0; }
.math-block {
  overflow-x: auto;
  margin: 1.5rem 0;
  padding: 1.15rem 1.25rem;
  border-left: .3rem solid var(--blue);
  background: var(--surface);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: clamp(.86rem, 2vw, 1rem);
  white-space: pre-wrap;
}
.grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 15rem), 1fr));
  margin-top: 1.5rem;
}
.card {
  padding: 1.15rem;
  border: 1px solid var(--line);
  background: var(--surface);
}
.card p { margin: 0; color: var(--muted); }
.card .tag {
  display: block;
  margin-bottom: .5rem;
  color: var(--blue);
  font-size: .7rem;
  letter-spacing: .09em;
  font-weight: 760;
  text-transform: uppercase;
}
.status-exact { border-top: .3rem solid var(--blue); }
.status-contact { border-top: .3rem solid var(--red); }
.status-supplied { border-top: .3rem solid var(--violet); }
.status-future { border-top: .3rem solid var(--green); }
table { width: 100%; border-collapse: collapse; margin: 1.5rem 0; background: var(--surface); }
th, td { padding: .72rem; text-align: left; vertical-align: top; border-bottom: 1px solid var(--line); }
th { font-size: .74rem; letter-spacing: .06em; text-transform: uppercase; }
code, .mono { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }
small { color: var(--muted); }
.list { padding-left: 1.15rem; }
.list li + li { margin-top: .7rem; }
.provenance { max-width: 49rem; color: var(--muted); }
.site-footer {
  width: min(var(--max), calc(100% - 2rem));
  margin: auto;
  padding: 2rem 0 3rem;
  color: var(--muted);
  font-size: .83rem;
}
.site-footer nav { margin-top: .7rem; display: flex; flex-wrap: wrap; gap: .75rem; }
.rule { height: 3px; width: 4rem; margin: 1.5rem 0; background: linear-gradient(90deg, var(--red), var(--blue), var(--violet)); }
@media (min-width: 48rem) {
  .header-inner { grid-template-columns: 1fr auto; align-items: center; }
  .primary-nav { justify-content: flex-end; }
}
@media (max-width: 38rem) {
  h1 { max-width: 12ch; }
  th, td { font-size: .87rem; }
  table { display: block; overflow-x: auto; }
}

/* R4: orientation, lineage, formalism, and library presentation */
:root {
  --ink: #17212b;
  --paper: #f4efe6;
  --surface: #fffdf8;
  --line: #c6bcae;
  --muted: #5d5b58;
  --blue: #2f5e99;
  --red: #ad4936;
  --violet: #614785;
  --green: #2f7569;
  --gold: #aa7622;
  --warm: #efe1c5;
  --max: 76rem;
}
body {
  background:
    radial-gradient(circle at 86% 0%, rgba(196, 148, 62, .11), transparent 22rem),
    radial-gradient(circle at 0% 34%, rgba(47, 94, 153, .08), transparent 25rem),
    var(--paper);
}
.site-header {
  position: sticky;
  top: 0;
  z-index: 5;
  background: color-mix(in srgb, var(--surface) 94%, transparent);
  backdrop-filter: blur(14px);
}
.header-inner { padding: .85rem 0 .72rem; }
.primary-nav { gap: .9rem; font-size: .74rem; }
.primary-nav a { padding: .22rem 0; }
.primary-nav a[aria-current="page"] { color: var(--red); border-bottom: 2px solid var(--red); }
.hero { padding-top: clamp(3.25rem, 8vw, 6.25rem); }
.hero-home {
  display: grid;
  gap: clamp(2rem, 7vw, 6rem);
  align-items: end;
  min-height: min(47rem, 83vh);
}
.hero-home h1 { max-width: 11ch; }
.hero-home .deck { max-width: 36rem; }
.home-orientation {
  align-self: stretch;
  display: grid;
  align-content: end;
  gap: 1.25rem;
  padding: 1.5rem;
  border: 1px solid var(--ink);
  background:
    linear-gradient(135deg, rgba(47, 94, 153, .11), rgba(255,253,248,.92) 58%),
    var(--surface);
}
.home-orientation h2 { max-width: 13ch; margin: 0; font-size: clamp(1.5rem, 3vw, 2.25rem); }
.orientation-steps {
  list-style: none;
  display: grid;
  gap: .85rem;
  padding: 0;
  margin: 0;
  counter-reset: orientation;
}
.orientation-steps li {
  display: grid;
  grid-template-columns: 2.15rem 1fr;
  gap: .6rem;
  align-items: start;
  color: var(--muted);
}
.orientation-steps li::before {
  counter-increment: orientation;
  content: "0" counter(orientation);
  color: var(--red);
  font-size: .72rem;
  font-weight: 800;
  letter-spacing: .08em;
  padding-top: .23rem;
}
.orientation-steps strong { display: block; color: var(--ink); font-size: .95rem; }
.home-mark {
  margin: 0;
  color: var(--blue);
  font-family: ui-serif, Georgia, Cambria, "Times New Roman", serif;
  font-size: 1.05rem;
}
.common-grid,
.path-grid,
.formalism-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 14rem), 1fr));
  margin-top: 1.75rem;
}
.common-card,
.path-card {
  min-height: 12rem;
  padding: 1.25rem;
  border: 1px solid var(--line);
  background: var(--surface);
}
.common-card:nth-child(1) { border-top: .32rem solid var(--blue); }
.common-card:nth-child(2) { border-top: .32rem solid var(--red); }
.common-card:nth-child(3) { border-top: .32rem solid var(--gold); }
.common-card:nth-child(4) { border-top: .32rem solid var(--green); }
.common-card p,
.path-card p { color: var(--muted); margin: 0; }
.lineage-section { overflow: hidden; }
.lineage-intro {
  display: flex;
  flex-wrap: wrap;
  align-items: end;
  justify-content: space-between;
  gap: 1rem 2rem;
}
.lineage-intro p { max-width: 42rem; margin: 0; color: var(--muted); }
.lineage-deck {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(15rem, 20rem);
  gap: 1rem;
  overflow-x: auto;
  overscroll-behavior-inline: contain;
  scroll-snap-type: inline mandatory;
  padding: 1.5rem 0 1rem;
  scrollbar-color: var(--gold) transparent;
}
.lineage-card {
  scroll-snap-align: start;
  display: grid;
  grid-template-rows: 10rem auto;
  border: 1px solid var(--line);
  background: var(--surface);
  color: inherit;
  text-decoration: none;
}
.lineage-card:hover h3,
.lineage-card:focus-visible h3 { text-decoration: underline; text-underline-offset: .14em; }
.lineage-card img {
  width: 100%;
  height: 10rem;
  object-fit: cover;
  border-bottom: 1px solid var(--line);
  background: #e9e2d7;
}
.lineage-card > div { padding: 1rem; }
.lineage-card .date,
.book-card .date,
.field-card .field-label {
  display: block;
  margin-bottom: .45rem;
  color: var(--red);
  font-size: .7rem;
  font-weight: 780;
  letter-spacing: .09em;
  text-transform: uppercase;
}
.lineage-card p { margin: 0; color: var(--muted); font-size: .93rem; }
.release-band {
  display: grid;
  gap: 1.25rem;
  padding: clamp(1.35rem, 4vw, 2.25rem);
  border: 1px solid var(--ink);
  background: linear-gradient(120deg, #192a3c, #284a6b);
  color: #f8f4eb;
}
.release-band h2,
.release-band h3 { color: inherit; }
.release-band p { margin: 0; color: #e2e8ef; }
.release-band .kicker { color: #eec76b; }
.release-band .button { color: var(--ink); background: #f8f4eb; border-color: #f8f4eb; }
.release-band .button.secondary { color: #f8f4eb; background: transparent; border-color: #f8f4eb; }
.architecture-ledger {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 15rem), 1fr));
  margin-top: 1.5rem;
}
.architecture-ledger > div {
  padding: 1.15rem;
  border: 1px solid var(--line);
  background: var(--surface);
}
.architecture-ledger h3 { margin-bottom: .5rem; }
.architecture-ledger p { margin: 0; color: var(--muted); }
.library-title {
  padding: clamp(2.4rem, 6vw, 4.75rem) 0 clamp(1.2rem, 3vw, 2rem);
}
.library-title h1 { max-width: none; }
.shelf {
  padding: clamp(2.8rem, 7vw, 5rem) 0;
  border-bottom: 1px solid var(--line);
}
.shelf-intro { display: grid; gap: 1rem; max-width: 55rem; }
.shelf-intro p { margin: 0; color: var(--muted); }
.library-grid {
  display: grid;
  gap: 1.25rem;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 15.5rem), 1fr));
  margin-top: 1.75rem;
}
.book-card {
  display: grid;
  grid-template-rows: 13rem auto;
  min-height: 100%;
  border: 1px solid var(--line);
  background: var(--surface);
  box-shadow: 0 .5rem 1.4rem rgba(23,33,43,.055);
}
.book-cover {
  display: block;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
  background: #e6ddd0;
}
.book-cover img {
  width: 100%;
  height: 13rem;
  object-fit: cover;
  transition: transform .35s ease;
}
.book-card:hover .book-cover img { transform: scale(1.035); }
.book-cover.cover-type {
  display: grid;
  align-content: space-between;
  min-height: 13rem;
  padding: 1rem;
  color: #fbf8f1;
  text-decoration: none;
  background: linear-gradient(145deg, #233e61, #17212b);
}
.book-cover.cover-type .cover-kicker {
  color: #f2cb72;
  font-size: .67rem;
  font-weight: 780;
  letter-spacing: .12em;
  text-transform: uppercase;
}
.book-cover.cover-type strong {
  max-width: 9ch;
  color: inherit;
  font-family: ui-serif, Georgia, Cambria, "Times New Roman", serif;
  font-size: clamp(1.5rem, 3vw, 2.2rem);
  line-height: .95;
  letter-spacing: -.04em;
}
.book-cover.cover-red { background: linear-gradient(145deg, #9a4339, #4d222c); }
.book-cover.cover-green { background: linear-gradient(145deg, #39796d, #153f3b); }
.book-cover.cover-violet { background: linear-gradient(145deg, #67528c, #2d254c); }
.book-cover.cover-gold { background: linear-gradient(145deg, #b5812b, #5b3d1d); }
.book-card > div { display: grid; align-content: start; gap: .7rem; padding: 1rem; }
.book-card h3 { margin: 0; }
.book-card p { margin: 0; color: var(--muted); font-size: .93rem; }
.book-actions {
  display: flex;
  flex-wrap: wrap;
  gap: .55rem .85rem;
  margin-top: .15rem;
  font-size: .83rem;
  font-weight: 690;
}
.shelf-notes {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 16rem), 1fr));
  margin-top: 1.5rem;
}
.shelf-note {
  padding: 1.15rem;
  border-left: .28rem solid var(--gold);
  background: rgba(255,253,248,.74);
}
.shelf-note p { margin: 0; color: var(--muted); }
.formalism-hero { max-width: 58rem; }
.reading-key {
  display: grid;
  gap: 1px;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 13rem), 1fr));
  margin-top: 1.75rem;
  border: 1px solid var(--line);
  background: var(--line);
}
.reading-key > div { padding: 1rem; background: var(--surface); }
.reading-key strong { display: block; margin-bottom: .3rem; font-size: .76rem; letter-spacing: .08em; text-transform: uppercase; }
.reading-key p { margin: 0; color: var(--muted); font-size: .92rem; }
.field-stack { display: grid; gap: 1.25rem; margin-top: 1.75rem; }
.field-card {
  display: grid;
  gap: 1.35rem;
  padding: clamp(1.2rem, 3vw, 1.75rem);
  border: 1px solid var(--line);
  background: var(--surface);
}
.field-card:nth-child(4n+1) { border-top: .32rem solid var(--blue); }
.field-card:nth-child(4n+2) { border-top: .32rem solid var(--red); }
.field-card:nth-child(4n+3) { border-top: .32rem solid var(--green); }
.field-card:nth-child(4n) { border-top: .32rem solid var(--gold); }
.field-card h3 { margin-bottom: .45rem; }
.field-card > div > p { margin: 0; color: var(--muted); }
.field-notes {
  display: grid;
  gap: .6rem 1rem;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 11rem), 1fr));
  margin: 0;
}
.field-notes div { padding-top: .65rem; border-top: 1px solid var(--line); }
.field-notes dt {
  color: var(--red);
  font-size: .68rem;
  font-weight: 780;
  letter-spacing: .09em;
  text-transform: uppercase;
}
.field-notes dd { margin: .22rem 0 0; color: var(--muted); font-size: .91rem; }
.native-strip {
  display: grid;
  gap: .7rem;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 10rem), 1fr));
  margin-top: 1rem;
}
.native-strip a {
  display: block;
  padding: .85rem;
  border: 1px solid var(--line);
  background: #faf7f1;
  text-decoration: none;
  font-size: .88rem;
}
.native-strip a strong { display: block; margin-bottom: .2rem; }
.native-strip a span { color: var(--muted); font-size: .8rem; }
.route-note {
  padding: 1.15rem;
  border-left: .28rem solid var(--violet);
  background: rgba(97,71,133,.06);
}
.route-note p { margin: 0; color: var(--muted); }
.quiet-footer { color: var(--muted); }
.ledger-hero { max-width: 63rem; }
.ledger-index {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 9rem), 1fr));
  gap: 1px;
  margin-top: 2.2rem;
  border: 1px solid var(--line);
  background: var(--line);
}
.ledger-index a {
  display: grid;
  gap: .18rem;
  padding: .9rem 1rem;
  background: var(--surface);
  color: var(--ink);
  font-weight: 760;
  text-decoration: none;
}
.ledger-index a:hover { background: #f0ece3; color: var(--blue); }
.ledger-index span,
.record-code,
.record-label {
  color: var(--red);
  font-size: .68rem;
  font-weight: 790;
  letter-spacing: .12em;
  text-transform: uppercase;
}
.ledger-section { padding-bottom: clamp(3.5rem, 8vw, 6rem); }
.record-card {
  position: relative;
  margin-top: 1.25rem;
  padding: clamp(1.25rem, 3.5vw, 2.4rem);
  overflow: hidden;
  border: 1px solid var(--line);
  border-top: .42rem solid var(--blue);
  background: var(--surface);
  box-shadow: 0 .55rem 1.4rem rgba(23,33,43,.045);
}
.record-card.record-violet { border-top-color: var(--violet); }
.record-card.record-green { border-top-color: var(--green); }
.record-card.record-red { border-top-color: var(--red); }
.record-card-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1.25rem;
}
.record-card-head h2 { max-width: 19ch; margin: .45rem 0 0; }
.record-card .record-code { margin: 0; }
.phase-mark {
  display: grid;
  width: 2.1rem;
  height: 2.1rem;
  flex: 0 0 2.1rem;
  place-items: center;
  border: 1px solid currentColor;
  border-radius: 50%;
  color: var(--blue);
  font-family: ui-serif, Georgia, Cambria, "Times New Roman", serif;
  font-size: 1.28rem;
  font-style: italic;
}
.record-violet .phase-mark { color: var(--violet); }
.record-green .phase-mark { color: var(--green); }
.record-red .phase-mark { color: var(--red); }
.record-form {
  margin: 1.5rem 0 0;
  padding: .85rem 1rem;
  overflow-x: auto;
  border-left: .26rem solid var(--blue);
  background: #f3f0e9;
  color: var(--ink);
  font-size: clamp(.9rem, 2vw, 1.04rem);
}
.record-violet .record-form { border-left-color: var(--violet); }
.record-green .record-form { border-left-color: var(--green); }
.record-red .record-form { border-left-color: var(--red); }
.record-read {
  max-width: 50rem;
  margin: 1.15rem 0 0;
  color: var(--muted);
  font-family: ui-serif, Georgia, Cambria, "Times New Roman", serif;
  font-size: clamp(1.12rem, 2.4vw, 1.42rem);
  line-height: 1.35;
}
.record-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 12.5rem), 1fr));
  gap: 1px;
  margin-top: 1.75rem;
  border: 1px solid var(--line);
  background: var(--line);
}
.record-grid section { padding: 1rem; background: #fbf9f4; }
.record-grid p { margin: 0; }
.record-grid .record-label { margin-bottom: .55rem; }
.record-grid section > p:last-child { color: var(--muted); font-size: .93rem; }
.record-links {
  display: flex;
  flex-wrap: wrap;
  gap: .65rem 1rem;
  margin-top: 1.25rem;
  font-size: .83rem;
  font-weight: 730;
}
.record-links a { color: var(--ink); }
.record-links a:hover { color: var(--blue); }
.ledger-next { border-bottom: 0; }
.architecture-ledger > a {
  display: block;
  padding: 1.15rem;
  border: 1px solid var(--line);
  background: var(--surface);
  color: inherit;
  text-decoration: none;
}
.architecture-ledger > a:hover { border-color: var(--blue); box-shadow: 0 .4rem 1.1rem rgba(23,33,43,.075); }
.architecture-ledger > a h3 { margin-bottom: .5rem; }
.architecture-ledger > a p { margin: 0; color: var(--muted); }
.card-link {
  display: block;
  min-height: 100%;
  padding: 1.15rem;
  border: 1px solid var(--line);
  color: inherit;
  text-decoration: none;
}
.card-link:hover { border-color: var(--blue); box-shadow: 0 .4rem 1.1rem rgba(23,33,43,.075); }
.card-link.status-exact { border-top: .32rem solid var(--blue); }
.card-link.status-supplied { border-top: .32rem solid var(--violet); }
.card-link.status-contact { border-top: .32rem solid var(--red); }
.card-link.status-future { border-top: .32rem solid var(--green); }
.card-link p { margin-bottom: 0; }
@media (max-width: 34rem) {
  .record-card { padding: 1.1rem; }
  .record-card-head { gap: .75rem; }
  .record-card-head h2 { font-size: 1.75rem; }
}
@media (min-width: 58rem) {
  .hero-home { grid-template-columns: minmax(0, 1.25fr) minmax(17rem, .75fr); }
  .release-band { grid-template-columns: 1.2fr .8fr; align-items: end; }
  .field-card { grid-template-columns: minmax(0, 1.1fr) minmax(18rem, .9fr); }
}