:root {
  --paper: #f2eee5;
  --paper-deep: #e7dfd1;
  --ink: #171815;
  --ink-soft: #505149;
  --line: #c8bfae;
  --line-strong: #968b7c;
  --signal: #c44732;
  --signal-dark: #8e2e20;
  --blue: #214e68;
  --blue-pale: #dce6e8;
  --white: #fffefa;
  --display: "Iowan Old Style", "Baskerville", "Palatino Linotype", Palatino, Georgia, serif;
  --sans: "Avenir Next", Avenir, "Century Gothic", "Gill Sans", sans-serif;
  --mono: "SFMono-Regular", "Cascadia Code", "Roboto Mono", Consolas, monospace;
  --max: 1200px;
  --gutter: clamp(1.25rem, 4vw, 4rem);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 14% 8%, rgb(255 255 255 / 48%) 0 10rem, transparent 28rem),
    linear-gradient(90deg, transparent 0 calc(100% - 1px), rgb(23 24 21 / 3%) 100%),
    var(--paper);
  font-family: var(--sans);
  font-size: 1rem;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  content: "";
  opacity: 0.22;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 180 180' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.92' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='.12'/%3E%3C/svg%3E");
}

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

a {
  color: inherit;
  text-decoration-color: rgb(23 24 21 / 40%);
  text-underline-offset: 0.2em;
}

a:hover {
  text-decoration-color: currentColor;
}

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

button,
a {
  -webkit-tap-highlight-color: transparent;
}

button:focus-visible,
a:focus-visible,
[tabindex]:focus-visible {
  outline: 3px solid var(--signal);
  outline-offset: 4px;
}

.skip-link {
  position: fixed;
  top: 0.75rem;
  left: 0.75rem;
  z-index: 100;
  padding: 0.65rem 0.9rem;
  color: var(--white);
  background: var(--ink);
  transform: translateY(-150%);
}

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

.site-header {
  position: relative;
  z-index: 10;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  width: min(calc(100% - (2 * var(--gutter))), var(--max));
  min-height: 5.4rem;
  margin: 0 auto;
  border-bottom: 1px solid var(--ink);
}

.wordmark {
  display: inline-flex;
  gap: 0.65rem;
  align-items: center;
  width: max-content;
  font-weight: 650;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.wordmark-mark {
  display: inline-grid;
  width: 2.1rem;
  height: 2.1rem;
  place-items: center;
  color: var(--white);
  background: var(--signal);
  font-family: var(--display);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  line-height: 1;
}

.site-header nav {
  display: flex;
  gap: clamp(1rem, 2.5vw, 2.2rem);
  font-size: 0.78rem;
  font-weight: 650;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.site-header nav a,
.header-paper {
  text-decoration: none;
}

.site-header nav a {
  position: relative;
}

.site-header nav a::after {
  position: absolute;
  right: 0;
  bottom: -0.35rem;
  left: 0;
  height: 1px;
  content: "";
  background: currentColor;
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 180ms ease;
}

.site-header nav a:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.header-paper {
  justify-self: end;
  font-size: 0.86rem;
  font-weight: 650;
}

.hero,
.method,
.evidence,
.limits,
.citation,
footer {
  width: min(calc(100% - (2 * var(--gutter))), var(--max));
  margin-inline: auto;
}

.hero {
  padding: clamp(3rem, 7vw, 6.6rem) 0 clamp(4rem, 8vw, 8rem);
}

.hero-kicker {
  display: flex;
  justify-content: space-between;
  margin-bottom: clamp(2.4rem, 5vw, 4.5rem);
  color: var(--ink-soft);
  font-size: 0.72rem;
  font-weight: 650;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(17rem, 23rem);
  gap: clamp(3rem, 8vw, 7.5rem);
  align-items: end;
}

.eyebrow {
  margin: 0 0 0.9rem;
  color: var(--signal-dark);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1,
h2,
h3 {
  font-family: var(--display);
  font-weight: 600;
}

h1 {
  max-width: 14ch;
  margin-bottom: 1.8rem;
  font-size: clamp(3.5rem, 8vw, 7.4rem);
  letter-spacing: -0.065em;
  line-height: 0.86;
}

h1 > span {
  display: block;
  max-width: 19ch;
  margin-top: 0.45em;
  color: var(--ink-soft);
  font-family: var(--sans);
  font-size: clamp(1.12rem, 2.1vw, 1.8rem);
  font-weight: 500;
  letter-spacing: -0.035em;
  line-height: 1.15;
}

.deck {
  max-width: 43rem;
  margin-bottom: 2rem;
  font-family: var(--display);
  font-size: clamp(1.18rem, 2.15vw, 1.65rem);
  line-height: 1.45;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-bottom: 1.7rem;
}

.button {
  display: inline-flex;
  min-height: 3rem;
  align-items: center;
  justify-content: center;
  padding: 0.7rem 1.1rem;
  border: 1px solid var(--ink);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-decoration: none;
  text-transform: uppercase;
  transition:
    color 160ms ease,
    background 160ms ease,
    transform 160ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button-primary {
  color: var(--white);
  background: var(--ink);
}

.button-primary:hover {
  background: var(--signal-dark);
}

.button-secondary:hover {
  color: var(--paper);
  background: var(--blue);
}

.authors {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem 0.7rem;
  color: var(--ink-soft);
  font-size: 0.9rem;
}

.hero-ledger {
  border-top: 5px solid var(--signal);
  border-bottom: 1px solid var(--ink);
}

.ledger-label {
  margin: 0;
  padding: 0.8rem 0;
  border-bottom: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.hero-ledger dl {
  margin: 0;
}

.hero-ledger dl > div {
  display: grid;
  grid-template-columns: 6rem 1fr;
  gap: 1rem;
  align-items: center;
  padding: 1rem 0;
  border-bottom: 1px solid var(--line);
}

.hero-ledger dt {
  font-family: var(--display);
  font-size: 2.2rem;
  font-weight: 600;
  letter-spacing: -0.05em;
}

.hero-ledger dd {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.84rem;
  line-height: 1.45;
}

.ledger-note {
  margin: 0;
  padding: 1rem 0;
  color: var(--signal-dark);
  font-family: var(--display);
  font-size: 0.95rem;
  line-height: 1.45;
}

.section-grid {
  display: grid;
  grid-template-columns: minmax(3.5rem, 0.2fr) minmax(0, 1.4fr) minmax(16rem, 0.65fr);
  gap: clamp(1.5rem, 4vw, 4rem);
  width: min(100%, 1500px);
  margin-inline: auto;
  padding: clamp(4rem, 8vw, 8rem) var(--gutter);
  color: var(--white);
  background: var(--ink);
}

.section-index {
  color: #928f84;
  font-family: var(--display);
  font-size: clamp(2rem, 4vw, 4.3rem);
}

.question .eyebrow {
  color: #e87b65;
}

.question h2 {
  max-width: 20ch;
  margin: 0;
  font-size: clamp(2.2rem, 4.8vw, 4.8rem);
  letter-spacing: -0.045em;
  line-height: 1.02;
}

.question-answer {
  align-self: end;
  margin: 0;
  color: #d8d4ca;
  font-family: var(--display);
  font-size: clamp(1rem, 1.5vw, 1.25rem);
}

.definition {
  display: grid;
  grid-template-columns: minmax(9rem, 0.35fr) minmax(0, 1fr) minmax(15rem, 0.5fr);
  gap: clamp(2rem, 5vw, 5rem);
  width: min(100%, 1500px);
  margin: 0 auto;
  padding: clamp(3.5rem, 6vw, 6rem) var(--gutter);
  background: var(--signal);
}

.definition-label {
  padding-top: 0.6rem;
  color: #53170e;
  font-size: 0.72rem;
  font-weight: 750;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.definition h2 {
  margin-bottom: 1rem;
  font-size: clamp(2.5rem, 5vw, 5.2rem);
  letter-spacing: -0.055em;
  line-height: 1;
}

.definition h2 span {
  display: block;
  margin-top: 0.7rem;
  font-family: var(--sans);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.08em;
}

.definition-copy p,
.definition-stat span {
  max-width: 45rem;
  margin: 0;
  color: #3d120b;
}

.definition-copy p {
  font-family: var(--display);
  font-size: clamp(1.08rem, 1.6vw, 1.35rem);
}

.definition-stat {
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  border-left: 1px solid rgb(61 18 11 / 38%);
  padding-left: clamp(1.5rem, 3vw, 3rem);
}

.definition-stat strong {
  display: block;
  font-family: var(--display);
  font-size: clamp(3.5rem, 7vw, 6.8rem);
  font-weight: 600;
  letter-spacing: -0.07em;
  line-height: 0.95;
}

.definition-stat span {
  margin-top: 1rem;
  font-size: 0.82rem;
  line-height: 1.5;
}

.method,
.evidence,
.limits,
.citation {
  padding: clamp(5rem, 10vw, 9rem) 0;
}

.section-heading {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(16rem, 0.55fr);
  gap: clamp(2rem, 8vw, 8rem);
  align-items: end;
  margin-bottom: clamp(3rem, 6vw, 5rem);
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--ink);
}

.section-heading h2,
.limits h2,
.citation h2 {
  max-width: 18ch;
  margin: 0;
  font-size: clamp(2.6rem, 5.8vw, 5.8rem);
  letter-spacing: -0.055em;
  line-height: 0.98;
}

.section-heading > p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.94rem;
}

.paper-figure {
  margin: 0;
  padding: clamp(0.8rem, 2vw, 1.5rem);
  background: var(--white);
  box-shadow: 0 18px 60px rgb(49 39 25 / 10%);
}

.paper-figure img {
  width: 100%;
}

.paper-figure figcaption {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1.1rem;
  margin-top: 1rem;
  padding-top: 0.8rem;
  border-top: 1px solid var(--line);
  color: var(--ink-soft);
  font-family: var(--display);
  font-size: 0.9rem;
  line-height: 1.5;
}

.paper-figure figcaption span {
  color: var(--signal-dark);
  font-family: var(--sans);
  font-size: 0.68rem;
  font-weight: 750;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.wide-figure {
  margin-bottom: clamp(3rem, 6vw, 5rem);
}

.method-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--ink);
}

.method-steps li {
  position: relative;
  min-height: 21rem;
  padding: 1.5rem clamp(1.2rem, 3vw, 2.5rem) 2.5rem;
  border-right: 1px solid var(--line);
}

.method-steps li:first-child {
  padding-left: 0;
}

.method-steps li:last-child {
  padding-right: 0;
  border-right: 0;
}

.step-number {
  display: block;
  margin-bottom: clamp(3rem, 8vw, 7rem);
  color: var(--signal);
  font-family: var(--display);
  font-size: 1.1rem;
}

.method-steps h3 {
  margin-bottom: 0.7rem;
  font-size: 2rem;
  letter-spacing: -0.035em;
}

.method-steps p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.9rem;
}

.evidence {
  border-top: 1px solid var(--line-strong);
}

.evidence-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.45fr) minmax(15rem, 0.55fr);
  gap: clamp(1.5rem, 4vw, 4rem);
  align-items: stretch;
  margin-bottom: clamp(3rem, 6vw, 5rem);
}

.evidence-callout {
  position: relative;
  display: flex;
  min-height: 100%;
  flex-direction: column;
  justify-content: flex-end;
  overflow: hidden;
  padding: clamp(1.5rem, 3vw, 3rem);
  color: var(--white);
  background: var(--blue);
}

.callout-mark {
  position: absolute;
  top: -2rem;
  left: 1.1rem;
  color: rgb(255 255 255 / 12%);
  font-family: var(--display);
  font-size: 13rem;
  line-height: 1;
}

.evidence-callout p {
  position: relative;
  margin: 0;
  font-family: var(--display);
  font-size: clamp(1.55rem, 3vw, 2.65rem);
  line-height: 1.15;
}

.table-wrap {
  overflow-x: auto;
  margin-bottom: clamp(4rem, 8vw, 7rem);
  border-top: 2px solid var(--ink);
  border-bottom: 2px solid var(--ink);
}

table {
  width: 100%;
  min-width: 850px;
  border-collapse: collapse;
  font-size: 0.84rem;
}

caption {
  padding: 1rem 0;
  color: var(--ink-soft);
  font-family: var(--display);
  font-size: 1rem;
  text-align: left;
}

th,
td {
  padding: 1.05rem 0.8rem;
  border-top: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

thead th {
  color: var(--ink-soft);
  font-size: 0.67rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

tbody th {
  width: 11rem;
  font-family: var(--display);
  font-size: 1rem;
}

tbody td:nth-child(2) {
  color: var(--signal-dark);
}

tbody td:last-child {
  max-width: 24rem;
  color: var(--ink-soft);
}

.composition {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(18rem, 0.65fr);
  gap: clamp(2.5rem, 7vw, 7rem);
  margin-bottom: clamp(4rem, 8vw, 7rem);
  padding: clamp(2rem, 5vw, 4.5rem);
  color: var(--white);
  background: var(--ink);
}

.composition h3 {
  max-width: 17ch;
  margin-bottom: 1.3rem;
  font-size: clamp(2.1rem, 4.2vw, 4.1rem);
  letter-spacing: -0.045em;
  line-height: 1;
}

.composition-copy > p:not(.eyebrow) {
  max-width: 42rem;
  color: #d8d4ca;
}

.composition .eyebrow {
  color: #e87b65;
}

.composition .boundary {
  padding-top: 1rem;
  border-top: 1px solid #55564f;
  font-family: var(--display);
  font-size: 1.08rem;
}

.composition-ledger {
  margin: 0;
  border-top: 1px solid #72736a;
}

.composition-ledger div {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 1rem;
  padding: 1rem 0;
  border-bottom: 1px solid #55564f;
}

.composition-ledger dt {
  color: #bebbb2;
  font-size: 0.78rem;
}

.composition-ledger dd {
  margin: 0;
  font-family: var(--display);
}

.composition-ledger strong {
  color: #f1846d;
}

.secondary-figure {
  max-width: 62rem;
  margin-inline: auto;
}

.limits {
  display: grid;
  grid-template-columns: minmax(16rem, 0.65fr) minmax(0, 1.35fr);
  gap: clamp(3rem, 8vw, 8rem);
  border-top: 1px solid var(--line-strong);
}

.limits-intro > p:last-child {
  max-width: 27rem;
  margin-top: 1.5rem;
  color: var(--ink-soft);
}

.limits-list {
  border-top: 2px solid var(--ink);
}

.limits-list article {
  display: grid;
  grid-template-columns: 2.5rem minmax(11rem, 0.45fr) minmax(0, 1fr);
  gap: 1.2rem;
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--line);
}

.limits-list article > span {
  color: var(--signal-dark);
  font-family: var(--display);
}

.limits-list h3,
.limits-list p {
  margin: 0;
}

.limits-list h3 {
  font-size: 1.35rem;
}

.limits-list p {
  color: var(--ink-soft);
  font-size: 0.88rem;
}

.limits-list .availability-card {
  margin-inline: -1rem;
  padding-inline: 1rem;
  color: var(--white);
  background: var(--signal-dark);
  border: 0;
}

.limits-list .availability-card > span,
.limits-list .availability-card p {
  color: #f0d8d2;
}

.citation {
  display: grid;
  grid-template-columns: minmax(18rem, 0.55fr) minmax(0, 1.25fr);
  gap: clamp(3rem, 7vw, 7rem);
  border-top: 1px solid var(--line-strong);
}

.citation-copy > p:not(.eyebrow) {
  max-width: 28rem;
  margin-top: 1.5rem;
  color: var(--ink-soft);
}

.citation-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem 1.2rem;
  margin-top: 2rem;
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.code-card {
  align-self: end;
  overflow: hidden;
  color: #f0ece2;
  background: var(--ink);
}

.code-toolbar {
  display: grid;
  grid-template-columns: 1fr auto minmax(0, auto);
  gap: 0.8rem;
  align-items: center;
  min-height: 3.2rem;
  padding: 0.6rem 1rem;
  border-bottom: 1px solid #44453f;
  color: #b7b4aa;
  font-size: 0.68rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.code-toolbar button {
  padding: 0.45rem 0.7rem;
  color: var(--ink);
  background: #e7dfd1;
  border: 0;
  cursor: pointer;
  font: inherit;
  font-weight: 750;
  letter-spacing: inherit;
  text-transform: inherit;
}

.code-toolbar button:hover {
  background: #f1846d;
}

.copy-status {
  min-width: 5.5rem;
  color: #f1846d;
  text-align: right;
}

pre {
  margin: 0;
  overflow-x: auto;
  padding: clamp(1.3rem, 3vw, 2.5rem);
}

code {
  font-family: var(--mono);
  font-size: 0.78rem;
  line-height: 1.75;
}

footer {
  display: flex;
  justify-content: space-between;
  gap: 2rem;
  align-items: flex-end;
  padding: 2rem 0 3rem;
  border-top: 1px solid var(--ink);
}

footer > div:first-child {
  display: flex;
  gap: 1rem;
  align-items: center;
}

footer p {
  max-width: 32rem;
  margin: 0;
  color: var(--ink-soft);
  font-size: 0.75rem;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 1.2rem;
  justify-content: flex-end;
  font-size: 0.72rem;
  font-weight: 650;
}

@media (max-width: 900px) {
  .site-header {
    grid-template-columns: 1fr auto;
  }

  .site-header nav {
    display: none;
  }

  .hero-grid,
  .section-heading,
  .limits,
  .citation {
    grid-template-columns: 1fr;
  }

  .hero-ledger {
    max-width: 38rem;
  }

  .section-grid {
    grid-template-columns: 4rem 1fr;
  }

  .question-answer {
    grid-column: 2;
    max-width: 38rem;
  }

  .definition {
    grid-template-columns: 0.35fr 1fr;
  }

  .definition-stat {
    grid-column: 2;
    border-top: 1px solid rgb(61 18 11 / 38%);
    border-left: 0;
    padding-top: 1.5rem;
    padding-left: 0;
  }

  .evidence-layout,
  .composition {
    grid-template-columns: 1fr;
  }

  .evidence-callout {
    min-height: 22rem;
  }
}

@media (max-width: 680px) {
  body {
    font-size: 0.95rem;
  }

  .site-header {
    min-height: 4.7rem;
  }

  .header-paper {
    font-size: 0.76rem;
  }

  .hero-kicker {
    gap: 1rem;
    font-size: 0.6rem;
  }

  h1 {
    font-size: clamp(3.2rem, 17vw, 5.1rem);
  }

  .section-grid,
  .definition {
    grid-template-columns: 1fr;
  }

  .section-index {
    font-size: 2rem;
  }

  .question-answer,
  .definition-stat {
    grid-column: 1;
  }

  .definition-stat {
    margin-top: 1rem;
  }

  .method-steps {
    grid-template-columns: 1fr;
  }

  .method-steps li,
  .method-steps li:first-child,
  .method-steps li:last-child {
    min-height: auto;
    padding: 1.6rem 0 2.2rem;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .method-steps li:last-child {
    border-bottom: 0;
  }

  .step-number {
    margin-bottom: 1.5rem;
  }

  .paper-figure {
    margin-inline: calc(var(--gutter) * -0.5);
  }

  .paper-figure figcaption {
    grid-template-columns: 1fr;
    gap: 0.35rem;
  }

  .composition {
    margin-inline: calc(var(--gutter) * -0.5);
    padding-inline: calc(var(--gutter) * 0.75);
  }

  .limits-list article {
    grid-template-columns: 2rem 1fr;
  }

  .limits-list article p {
    grid-column: 2;
  }

  .code-toolbar {
    grid-template-columns: 1fr auto;
  }

  .copy-status {
    grid-column: 1 / -1;
    min-height: 1em;
    text-align: left;
  }

  footer {
    align-items: flex-start;
    flex-direction: column;
  }

  .footer-links {
    justify-content: flex-start;
  }
}

@media (prefers-reduced-motion: no-preference) {
  .hero-copy > *,
  .hero-ledger {
    animation: reveal 700ms both;
  }

  .hero-copy > :nth-child(2) {
    animation-delay: 70ms;
  }

  .hero-copy > :nth-child(3) {
    animation-delay: 140ms;
  }

  .hero-copy > :nth-child(4) {
    animation-delay: 210ms;
  }

  .hero-copy > :nth-child(5),
  .hero-ledger {
    animation-delay: 280ms;
  }

  @keyframes reveal {
    from {
      opacity: 0;
      transform: translateY(16px);
    }

    to {
      opacity: 1;
      transform: translateY(0);
    }
  }
}

@media print {
  body {
    background: white;
  }

  body::before,
  .site-header,
  .hero-actions,
  .code-toolbar button,
  footer {
    display: none;
  }

  .hero,
  .method,
  .evidence,
  .limits,
  .citation {
    width: 100%;
  }

  .question,
  .definition,
  .composition,
  .code-card {
    break-inside: avoid;
  }
}