:root {
  color-scheme: light;
  --paper: #f7f6f1;
  --ink: #171d1d;
  --ink-soft: #344542;
  --muted: #4d605c;
  --signal: #2f6963;
  --line: rgba(23, 29, 29, 0.22);
  --line-strong: rgba(23, 29, 29, 0.4);
  --page-gutter: clamp(1rem, 5vw, 5.5rem);
  --page-max: 1240px;
  --sans: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
}

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

html {
  scroll-behavior: smooth;
}

body {
  min-width: 320px;
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1rem;
  line-height: 1.55;
  text-rendering: optimizeLegibility;
}

::selection {
  background: var(--signal);
  color: var(--paper);
}

.page-width {
  width: min(100%, var(--page-max));
  margin-inline: auto;
  padding-inline: var(--page-gutter);
}

:where(a) {
  color: inherit;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}

:where(a:hover) {
  color: var(--signal);
}

:where(a:focus-visible),
.skip-link:focus-visible {
  outline: 3px solid var(--signal);
  outline-offset: 4px;
}

.skip-link {
  position: fixed;
  z-index: 10;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.55rem 0.75rem;
  background: var(--ink);
  color: var(--paper);
  transform: translateY(-160%);
  transition: transform 160ms ease-out;
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  border-bottom: 1px solid var(--line-strong);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  padding-top: 1.2rem;
  padding-bottom: 1.15rem;
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  width: fit-content;
  color: var(--ink);
  font-size: 0.92rem;
  font-weight: 720;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.wordmark__mark {
  display: inline-grid;
  width: 1.85rem;
  height: 1.85rem;
  place-items: center;
  border: 1px solid var(--ink);
  color: var(--signal);
  font-family: var(--mono);
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: -0.1em;
  line-height: 1;
}

.section-nav ul {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: clamp(0.8rem, 2.8vw, 2.1rem);
  padding: 0;
  margin: 0;
  list-style: none;
}

.section-nav a {
  display: inline-flex;
  align-items: center;
  min-height: 2.75rem;
  padding: 0.7rem 0.25rem;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  line-height: 1.35;
  text-decoration-color: var(--signal);
  text-underline-offset: 0.35em;
}

.section-nav a:hover {
  color: var(--ink);
}

.hero {
  padding-top: clamp(3.75rem, 9vw, 8rem);
  padding-bottom: clamp(3.5rem, 7vw, 6.5rem);
}

.hero__body {
  min-width: 0;
}

.hero h1,
.section h2 {
  max-width: 14ch;
  margin: 0;
  font-weight: 650;
  letter-spacing: -0.04em;
  line-height: 0.99;
  text-wrap: balance;
}

.hero h1 {
  max-width: 11ch;
  font-size: clamp(2.7rem, 7.3vw, 5.6rem);
}

.hero__lede {
  max-width: 62ch;
  margin: clamp(1.7rem, 3.2vw, 2.6rem) 0 0;
  color: var(--ink-soft);
  font-size: clamp(1.03rem, 1.5vw, 1.24rem);
  line-height: 1.55;
}

.proof-rail,
.fact-rail {
  display: grid;
  gap: clamp(1rem, 3vw, 2.5rem);
  padding: 0;
  margin: 0;
}

.proof-rail {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin-top: clamp(2.75rem, 5vw, 4.75rem);
  border-top: 1px solid var(--line-strong);
  border-bottom: 1px solid var(--line-strong);
}

.proof-rail__item {
  min-width: 0;
  padding: 1.05rem 0 1.2rem;
}

.proof-rail dt,
.fact-rail dt,
.scope-list dt,
.diagram-label {
  color: var(--signal);
  font-family: var(--mono);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  line-height: 1.35;
  text-transform: uppercase;
}

.proof-rail dd {
  max-width: 24ch;
  margin: 0.55rem 0 0;
  font-size: 0.9rem;
  line-height: 1.48;
}

.section {
  padding-top: clamp(4.5rem, 8vw, 7.75rem);
  padding-bottom: clamp(4.5rem, 8vw, 7.75rem);
  scroll-margin-top: 1rem;
}

.section + .section {
  border-top: 1px solid var(--line);
}

.section__layout {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(16rem, 0.95fr);
  gap: clamp(2.25rem, 7vw, 7rem);
  align-items: start;
}

.section h2 {
  max-width: 14ch;
  font-size: clamp(2.25rem, 5vw, 4.35rem);
}

.section__copy,
.section__signal {
  min-width: 0;
}

.section__copy--wide {
  max-width: 70ch;
}

.section-intro,
.section-copy {
  max-width: 58ch;
  color: var(--ink-soft);
  font-size: 1.05rem;
  line-height: 1.62;
}

.section-intro {
  margin: clamp(1.5rem, 3vw, 2.4rem) 0 0;
}

.section-copy {
  margin: 1.2rem 0 0;
}

.field-figure {
  max-width: 34rem;
  margin: 0;
  padding: 0.75rem 0.5rem;
}

.field-figure__art {
  display: block;
  width: 100%;
  height: auto;
  overflow: visible;
}

.diagram-line {
  fill: none;
  stroke: var(--ink-soft);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 2.5;
}

.diagram-node {
  fill: var(--paper);
  stroke: var(--ink);
  stroke-width: 2;
}

.diagram-node--signal {
  fill: var(--signal);
  stroke: var(--signal);
}

.diagram-label {
  fill: var(--ink);
  font-size: 13px;
  text-anchor: middle;
  dominant-baseline: middle;
}

.diagram-label--inverse {
  fill: var(--paper);
}

.fact-rail {
  gap: 0;
  margin-top: 1.25rem;
  border-top: 1px solid var(--line-strong);
}

.fact-rail__item {
  display: grid;
  grid-template-columns: minmax(6rem, 0.45fr) minmax(0, 1fr);
  gap: 1.25rem;
  padding: 0.9rem 0;
  border-bottom: 1px solid var(--line);
}

.fact-rail dd {
  max-width: 34ch;
  margin: 0;
  line-height: 1.5;
}

.scope-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0 3rem;
  max-width: 70ch;
  padding: 0;
  margin: clamp(3rem, 6vw, 5rem) 0 0;
}

.scope-list > div {
  padding: 1rem 0 1.15rem;
  border-top: 1px solid var(--line);
}

.scope-list > div:nth-last-child(-n + 2) {
  border-bottom: 1px solid var(--line);
}

.scope-list dd {
  max-width: 32ch;
  margin: 0.45rem 0 0;
  line-height: 1.5;
}

@media (max-width: 700px) {
  .site-header__inner {
    align-items: flex-start;
    flex-direction: column;
    gap: 1.1rem;
  }

  .section-nav ul {
    justify-content: flex-start;
    gap: 0.85rem 1.1rem;
  }

  .hero {
    padding-top: 3.5rem;
    padding-bottom: 3.8rem;
  }

  .hero h1 {
    max-width: 11ch;
    font-size: clamp(2.55rem, 12vw, 4.35rem);
  }

  .hero__lede {
    font-size: 1rem;
  }

  .proof-rail {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .proof-rail__item {
    padding: 0.95rem 0 1rem;
  }

  .section {
    padding-top: 4.2rem;
    padding-bottom: 4.2rem;
  }

  .section__layout {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .section h2 {
    max-width: 15ch;
    font-size: clamp(2.15rem, 10vw, 3.5rem);
  }

  .field-figure {
    max-width: 34rem;
    padding-top: 0;
  }

  .fact-rail__item {
    grid-template-columns: minmax(6rem, 0.35fr) minmax(0, 1fr);
    gap: 1rem;
  }

  .scope-list {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .scope-list > div:nth-last-child(-n + 2) {
    border-bottom: 0;
  }

  .scope-list > div:last-child {
    border-bottom: 1px solid var(--line);
  }
}

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

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}