:root {
  --paper: #f7f8f4;
  --white: #ffffff;
  --ink: #102f24;
  --muted: #52635b;
  --forest: #173b2d;
  --green: #26754b;
  --mint: #e6eee5;
  --border: #d3ded2;
  --amber: #b7791f;
  --amber-pale: #f4ead6;
  --serif: "Crimson Pro", Georgia, serif;
  --sans: Inter, Arial, sans-serif;
  --mono: "JetBrains Mono", Consolas, monospace;
  --gutter: clamp(1.25rem, 4.2vw, 4.75rem);
  --max: 90rem;
}

* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
}
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1rem;
  line-height: 1.6;
}
a {
  color: inherit;
}
a:focus-visible,
button:focus-visible {
  outline: 3px solid var(--amber);
  outline-offset: 4px;
}
.skip-link {
  position: fixed;
  left: 1rem;
  top: -5rem;
  z-index: 20;
  background: var(--ink);
  color: var(--white);
  padding: 0.7rem 1rem;
}
.skip-link:focus {
  top: 1rem;
}
.site-header {
  min-height: 5.5rem;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 2rem;
  padding: 1rem var(--gutter);
  border-bottom: 1px solid var(--border);
  max-width: var(--max);
  margin: 0 auto;
}
.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  font-size: 0.84rem;
  font-weight: 780;
  letter-spacing: 0.15em;
  text-decoration: none;
  width: fit-content;
}
.wordmark-mark {
  display: grid;
  place-items: center;
  width: 2rem;
  height: 2rem;
  border: 1px solid var(--green);
  font-family: var(--serif);
  font-size: 1.3rem;
  line-height: 1;
}
nav {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 2.5vw, 2.6rem);
}
nav a,
.nav-link {
  font-size: 0.78rem;
  font-weight: 650;
  text-decoration: none;
}
nav a:hover,
.nav-link:hover,
.text-link:hover {
  text-decoration: underline;
  text-underline-offset: 0.35rem;
}
.nav-link {
  justify-self: end;
}
main,
footer {
  max-width: var(--max);
  margin: 0 auto;
}
.hero {
  min-height: min(47rem, calc(100vh - 5.5rem));
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(22rem, 0.95fr);
  gap: clamp(3rem, 7vw, 8rem);
  align-items: center;
  padding: clamp(4rem, 8vw, 8rem) var(--gutter);
}
.eyebrow,
.section-number,
.version-note,
.ledger-label,
.ledger-caption,
.footer-state {
  margin: 0;
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.eyebrow {
  color: var(--green);
  font-weight: 720;
}
h1,
h2,
h3,
p {
  margin-top: 0;
}
h1 {
  margin: 1.2rem 0 1.5rem;
  font-family: var(--serif);
  font-size: clamp(4rem, 8vw, 8rem);
  font-weight: 500;
  line-height: 0.82;
  letter-spacing: -0.055em;
}
.dek {
  max-width: 42rem;
  color: var(--muted);
  font-size: clamp(1.05rem, 1.4vw, 1.3rem);
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1.4rem;
  margin: 2.2rem 0 2.5rem;
}
.button {
  display: inline-block;
  padding: 0.8rem 1.1rem;
  background: var(--forest);
  color: var(--white);
  border: 1px solid var(--forest);
  font-size: 0.82rem;
  font-weight: 680;
  text-decoration: none;
}
.button:hover {
  background: var(--green);
  border-color: var(--green);
}
.text-link {
  font-size: 0.82rem;
  font-weight: 680;
  text-decoration: none;
}
.version-note {
  color: var(--muted);
  line-height: 1.5;
}
.ledger {
  position: relative;
  padding: 2.5rem;
  border: 1px solid var(--border);
  background: linear-gradient(
    135deg,
    rgba(255, 255, 255, 0.84),
    rgba(230, 238, 229, 0.56)
  );
  box-shadow: 1.5rem 1.5rem 0 rgba(23, 59, 45, 0.07);
}
.ledger::before {
  content: "";
  position: absolute;
  inset: 1rem;
  border: 1px solid rgba(38, 117, 75, 0.18);
  pointer-events: none;
}
.ledger-label {
  margin-bottom: 1.6rem;
  color: var(--muted);
}
.receipt {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 2.4rem 1fr auto;
  align-items: center;
  gap: 1rem;
  padding: 1.05rem;
  background: var(--white);
  border: 1px solid var(--border);
}
.receipt-index {
  font-family: var(--mono);
  font-size: 0.68rem;
  color: var(--green);
}
.receipt strong,
.receipt small {
  display: block;
}
.receipt strong {
  font-family: var(--mono);
  font-size: 0.78rem;
}
.receipt small {
  color: var(--muted);
  font-size: 0.7rem;
}
.receipt code {
  font-family: var(--mono);
  font-size: 0.67rem;
  color: var(--muted);
}
.receipt-two {
  margin-left: 1.5rem;
}
.receipt-three {
  margin-left: 3rem;
}
.chain-link {
  height: 1.7rem;
  margin-left: 2.25rem;
  border-left: 1px solid var(--green);
}
.chain-link span {
  display: block;
  transform: translate(-3px, 1.15rem) rotate(45deg);
  width: 6px;
  height: 6px;
  border-right: 1px solid var(--green);
  border-bottom: 1px solid var(--green);
}
.ledger-caption {
  margin-top: 1.6rem;
  color: var(--muted);
  text-align: right;
}
.rule-top {
  border-top: 1px solid var(--border);
}
.premise,
.assurance,
.status,
.constellation {
  padding: clamp(4rem, 7vw, 7rem) var(--gutter);
}
.premise {
  display: grid;
  grid-template-columns: minmax(8rem, 0.35fr) minmax(0, 1fr);
  gap: 3rem;
}
.section-number {
  color: var(--green);
  font-weight: 680;
}
h2 {
  font-family: var(--serif);
  font-size: clamp(2.5rem, 5vw, 5rem);
  font-weight: 500;
  line-height: 0.95;
  letter-spacing: -0.035em;
}
.premise > div > p {
  max-width: 43rem;
  margin: 2rem 0 0 auto;
  color: var(--muted);
  font-size: 1.12rem;
}
.invariants,
.operators {
  padding: clamp(4rem, 7vw, 7rem) var(--gutter);
}
.section-heading {
  display: grid;
  grid-template-columns: minmax(8rem, 0.35fr) minmax(0, 0.75fr) minmax(
      15rem,
      0.45fr
    );
  gap: 3rem;
  align-items: start;
}
.section-heading h2 {
  font-size: clamp(2.4rem, 4vw, 4rem);
}
.section-heading > p:last-child {
  color: var(--muted);
}
.invariant-grid {
  list-style: none;
  padding: 0;
  margin: 4rem 0 0;
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  border-top: 1px solid var(--border);
}
.invariant-grid li {
  grid-column: span 2;
  min-height: 16rem;
  padding: 1.5rem;
  border-right: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.invariant-grid li:nth-child(4) {
  grid-column: 2 / span 2;
  border-left: 1px solid var(--border);
}
.invariant-grid li:last-child {
  grid-column: span 2;
}
.invariant-grid span {
  font-family: var(--mono);
  color: var(--green);
  font-size: 0.7rem;
}
.invariant-grid h3 {
  margin: 3.4rem 0 0.75rem;
  font-family: var(--serif);
  font-size: 1.7rem;
  font-weight: 550;
  line-height: 1;
}
.invariant-grid p {
  color: var(--muted);
  font-size: 0.9rem;
}
.operator-flow {
  margin-top: 4rem;
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr;
  align-items: center;
  gap: 1.25rem;
}
.operator-flow article {
  min-height: 14rem;
  padding: 1.6rem;
  background: var(--white);
  border: 1px solid var(--border);
}
.operator-flow code {
  color: var(--green);
  font-family: var(--mono);
  font-size: 0.78rem;
}
.operator-flow h3 {
  margin: 3.2rem 0 0.5rem;
  font-family: var(--serif);
  font-size: 1.8rem;
  font-weight: 550;
}
.operator-flow p {
  color: var(--muted);
  font-size: 0.9rem;
}
.flow-arrow {
  color: var(--green);
}
.assurance {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: clamp(3rem, 7vw, 8rem);
  align-items: center;
  background: var(--forest);
  color: var(--white);
}
.assurance .section-number {
  color: #a7d8b7;
}
.assurance h2 {
  margin-top: 1rem;
}
.assurance-copy > p:last-child {
  color: #d2dfd8;
}
.boundary-card {
  border: 1px solid rgba(255, 255, 255, 0.28);
}
.boundary-row {
  display: grid;
  grid-template-columns: 3rem 1fr;
  gap: 1rem;
  padding: 1.6rem;
}
.boundary-row + .boundary-row {
  border-top: 1px solid rgba(255, 255, 255, 0.28);
}
.boundary-row > span {
  font-family: var(--serif);
  font-size: 2rem;
  color: #a7d8b7;
}
.boundary-row p {
  margin: 0;
  color: #d2dfd8;
}
.boundary-row strong {
  color: var(--white);
}
.boundary-row.neutral {
  background: rgba(255, 255, 255, 0.06);
}
.status {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: clamp(3rem, 7vw, 8rem);
}
.status h2 {
  margin-top: 1rem;
}
.status-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  border-top: 1px solid var(--border);
  border-left: 1px solid var(--border);
}
.status-grid article {
  display: flex;
  gap: 1rem;
  padding: 1.2rem;
  border-right: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}
.status-dot {
  flex: 0 0 auto;
  width: 0.55rem;
  height: 0.55rem;
  margin-top: 0.35rem;
  border-radius: 50%;
  background: var(--green);
}
.status-dot.proposed {
  background: var(--amber);
}
.status-dot.legacy {
  background: var(--muted);
}
.status-grid h3 {
  margin: 0;
  font-size: 0.8rem;
}
.status-grid p {
  margin: 0.15rem 0 0;
  color: var(--muted);
  font-size: 0.8rem;
}
.status-note {
  grid-column: 2;
  color: var(--muted);
  margin-bottom: 0;
}
.constellation {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: clamp(3rem, 7vw, 8rem);
}
.constellation h2 {
  margin-top: 1rem;
  font-size: clamp(2.5rem, 4vw, 4rem);
}
.constellation > div > p:last-child {
  color: var(--muted);
}
.constellation-links {
  border-top: 1px solid var(--border);
}
.constellation-links a {
  display: flex;
  justify-content: space-between;
  gap: 2rem;
  padding: 0.95rem 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.82rem;
  font-weight: 680;
  text-decoration: none;
}
.constellation-links a:hover {
  padding-left: 0.5rem;
  color: var(--green);
}
.constellation-links span {
  color: var(--muted);
  font-weight: 450;
  text-align: right;
}
footer {
  display: grid;
  grid-template-columns: 0.5fr 1fr auto;
  align-items: center;
  gap: 2rem;
  padding: 2rem var(--gutter);
  border-top: 1px solid var(--border);
}
footer p {
  margin: 0;
  color: var(--muted);
  font-size: 0.75rem;
}
footer a {
  text-underline-offset: 0.2rem;
}
.footer-state {
  text-align: right;
}
.not-found {
  min-height: 100vh;
  display: grid;
  align-content: center;
  justify-items: start;
  gap: 1.3rem;
  padding: var(--gutter);
}
.not-found h1 {
  max-width: 55rem;
  margin: 0;
}
.not-found p {
  max-width: 36rem;
  color: var(--muted);
}

@media (max-width: 900px) {
  .site-header {
    grid-template-columns: 1fr auto;
  }
  nav {
    display: none;
  }
  .hero {
    grid-template-columns: 1fr;
  }
  .ledger {
    max-width: 40rem;
  }
  .section-heading {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  .invariant-grid {
    grid-template-columns: 1fr 1fr;
  }
  .invariant-grid li,
  .invariant-grid li:nth-child(4),
  .invariant-grid li:last-child {
    grid-column: span 1;
    border-left: 0;
  }
  .invariant-grid li:nth-child(odd) {
    border-left: 1px solid var(--border);
  }
  .operator-flow {
    grid-template-columns: 1fr;
  }
  .flow-arrow {
    transform: rotate(90deg);
    justify-self: center;
  }
  .assurance,
  .status,
  .constellation {
    grid-template-columns: 1fr;
  }
  .status-note {
    grid-column: 1;
  }
  footer {
    grid-template-columns: 1fr;
  }
  .footer-state {
    text-align: left;
  }
}

@media (max-width: 520px) {
  .site-header {
    min-height: 4.5rem;
    gap: 0.75rem;
  }
  .nav-link {
    font-size: 0.7rem;
  }
  h1 {
    font-size: clamp(3.5rem, 19vw, 5rem);
  }
  .hero {
    padding-top: 4rem;
  }
  .ledger {
    padding: 1.5rem 1rem;
    box-shadow: 0.75rem 0.75rem 0 rgba(23, 59, 45, 0.07);
  }
  .receipt {
    grid-template-columns: 2rem 1fr;
  }
  .receipt code {
    grid-column: 2;
  }
  .receipt-two {
    margin-left: 0.6rem;
  }
  .receipt-three {
    margin-left: 1.2rem;
  }
  .premise {
    grid-template-columns: 1fr;
    gap: 1rem;
  }
  .invariant-grid,
  .status-grid {
    grid-template-columns: 1fr;
  }
  .invariant-grid li,
  .invariant-grid li:nth-child(odd) {
    border-left: 1px solid var(--border);
  }
  .constellation-links a {
    display: block;
  }
  .constellation-links span {
    display: block;
    margin-top: 0.2rem;
    text-align: left;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}