:root {
  --paper: #f3efe4;
  --ink: #181a17;
  --forest: #164735;
  --forest-faint: #dce4d9;
  --oxblood: #7b2c2c;
  --rule: #b7b19f;
  --sans: Arial, Helvetica, sans-serif;
  --serif: Georgia, "Times New Roman", serif;
  --mono: "Courier New", Courier, monospace;
  color-scheme: light;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.65;
}
a { color: var(--forest); text-decoration-thickness: 1px; text-underline-offset: .18em; }
a:hover { color: var(--oxblood); }
a:focus-visible, button:focus-visible, summary:focus-visible {
  outline: 3px solid var(--oxblood);
  outline-offset: 4px;
}
.skip-link {
  position: fixed;
  z-index: 20;
  top: 1rem;
  left: 1rem;
  padding: .65rem 1rem;
  background: var(--ink);
  color: var(--paper);
  transform: translateY(-200%);
}
.skip-link:focus { transform: none; }

.masthead {
  min-height: 74vh;
  display: grid;
  grid-template-columns: minmax(110px, .5fr) minmax(260px, 440px) minmax(320px, 1.45fr);
  align-items: end;
  gap: clamp(1.5rem, 4vw, 5rem);
  padding: clamp(2rem, 6vw, 6rem);
  border-bottom: 1px solid var(--ink);
  position: relative;
  overflow: hidden;
}
.masthead::after {
  content: "";
  position: absolute;
  right: -8rem;
  top: -8rem;
  width: 23rem;
  height: 23rem;
  border: 1px solid var(--rule);
  border-radius: 50%;
  box-shadow: 0 0 0 4rem var(--paper), 0 0 0 calc(4rem + 1px) var(--rule);
  z-index: -1;
}
.masthead__mark {
  align-self: stretch;
  border-right: 1px solid var(--rule);
  display: flex;
  justify-content: space-between;
  flex-direction: column;
  color: var(--oxblood);
  font: 700 .72rem/1 var(--sans);
  letter-spacing: .16em;
  padding-right: 1rem;
}
.masthead__mark span:first-child { font: 3.5rem/1 var(--serif); }
.masthead__portrait-wrap { position: relative; }
.masthead__portrait-wrap::before {
  content: "Fig. A";
  position: absolute;
  top: .75rem;
  left: -1.4rem;
  color: var(--paper);
  background: var(--oxblood);
  padding: .15rem .6rem;
  font: .7rem/1.7 var(--sans);
  letter-spacing: .12em;
  z-index: 1;
}
.masthead__portrait {
  display: block;
  width: 100%;
  max-height: 62vh;
  aspect-ratio: 4 / 5;
  object-fit: cover;
  filter: saturate(.7) contrast(1.04);
  border: 1px solid var(--ink);
  box-shadow: 12px 12px 0 var(--forest);
}
.masthead__copy { padding-bottom: clamp(.5rem, 3vw, 3rem); }
.eyebrow, .section-kicker, .index, .title, .contact-line, .proposition__number,
.proposition__context, .proof-label, .lemma, .backlink, .skill-field, footer {
  font-family: var(--sans);
}
.eyebrow {
  max-width: 28rem;
  margin: 0 0 2rem;
  color: var(--oxblood);
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .14em;
  text-transform: uppercase;
}
h1 {
  max-width: 10ch;
  margin: 0;
  font-size: clamp(3.3rem, 7.4vw, 8.5rem);
  line-height: .84;
  letter-spacing: -.065em;
  font-weight: 500;
}
.title { max-width: 34rem; margin: 2rem 0; font-size: clamp(1rem, 2vw, 1.35rem); }
.contact-line { display: flex; flex-wrap: wrap; gap: .5rem 1.5rem; font-size: .88rem; }

.journal-layout {
  display: grid;
  grid-template-columns: minmax(210px, 300px) minmax(0, 920px);
  gap: clamp(2rem, 7vw, 8rem);
  max-width: 1440px;
  margin: auto;
  padding: 0 clamp(1.25rem, 5vw, 5rem);
}
.index {
  position: sticky;
  top: 0;
  height: 100vh;
  align-self: start;
  padding: 3.5rem 0 2rem;
  border-right: 1px solid var(--rule);
  font-size: .76rem;
  line-height: 1.35;
  overflow-y: auto;
}
.index__heading { margin: 0 2rem 1.3rem 0; font-weight: 700; letter-spacing: .13em; text-transform: uppercase; }
.index ol { margin: 0 2rem 1.8rem 0; padding: 0; list-style: none; counter-reset: index; }
.index nav:first-of-type li { border-top: 1px solid var(--rule); }
.index nav:first-of-type li:last-child { border-bottom: 1px solid var(--rule); }
.index nav:first-of-type a { display: flex; justify-content: space-between; padding: .65rem 0; text-decoration: none; }
.index nav:first-of-type a::after { content: "→"; color: var(--oxblood); }
.index a[aria-current="true"] { color: var(--oxblood); font-weight: 700; }
.index__note { margin: 1.7rem 2rem .7rem 0; font-style: italic; }
.proof-index a { display: grid; grid-template-columns: 1.7rem 1fr; gap: .4rem; padding: .32rem 0; text-decoration: none; }
.proof-index span { color: var(--oxblood); font-family: var(--mono); }
.view-switch { display: flex; margin-right: 2rem; }
.view-switch button {
  flex: 1;
  border: 1px solid var(--forest);
  padding: .5rem .25rem;
  background: transparent;
  color: var(--forest);
  font: inherit;
  cursor: pointer;
}
.view-switch button + button { border-left: 0; }
.view-switch button[aria-pressed="true"] { color: var(--paper); background: var(--forest); }

main { min-width: 0; }
main > section { padding: clamp(4.5rem, 10vw, 9rem) 0; border-bottom: 1px solid var(--ink); }
.section-kicker {
  display: flex;
  align-items: center;
  gap: 1rem;
  color: var(--oxblood);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .15em;
  text-transform: uppercase;
}
.section-kicker::after { content: ""; width: 4rem; border-top: 1px solid var(--oxblood); }
.section-kicker span { font-family: var(--mono); }
h2 { max-width: 13ch; margin: .8rem 0 2rem; font-size: clamp(2.8rem, 6vw, 5.6rem); font-weight: 400; line-height: .96; letter-spacing: -.045em; }
.section-intro { max-width: 40rem; margin: -1rem 0 4rem; font-style: italic; color: #45463f; }
.summary-copy { max-width: 47rem; font-size: clamp(1.2rem, 2.2vw, 1.55rem); line-height: 1.6; }
.summary-copy p:first-child::first-letter { float: left; margin: .08em .12em 0 0; color: var(--oxblood); font-size: 4.4em; line-height: .7; }
.endmark { display: block; margin-top: 2rem; color: var(--forest); font-size: .7rem; text-align: right; }

.propositions { counter-reset: proof; }
.proposition {
  position: relative;
  padding: clamp(3rem, 7vw, 6rem) 0;
  border-top: 1px solid var(--rule);
  scroll-margin-top: 1rem;
}
.proposition::before {
  content: "";
  position: absolute;
  left: -2.5rem;
  top: 5.8rem;
  width: 1.2rem;
  height: 1.2rem;
  border: 1px solid var(--forest);
  transform: rotate(45deg);
}
.proposition__header { display: grid; grid-template-columns: 10rem minmax(0, 1fr); gap: .2rem 2rem; }
.proposition__number { grid-row: span 2; margin: .5rem 0 0; color: var(--oxblood); font-size: .72rem; letter-spacing: .12em; text-transform: uppercase; }
.proposition h3 { margin: 0; font-size: clamp(1.8rem, 3.5vw, 3rem); line-height: 1.05; font-weight: 400; }
.proposition__context { margin: .6rem 0 0; font-size: .84rem; }
.proposition__context span { padding: 0 .4rem; color: var(--rule); }
.construction { display: grid; grid-template-columns: 10rem minmax(0, 1fr); gap: 2rem; margin-top: 2.4rem; }
.proof-label { margin: .3rem 0 0; color: var(--forest); font-size: .7rem; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; }
.construction ol { margin: 0; padding: 0; list-style: none; counter-reset: result; }
.construction li { counter-increment: result; position: relative; padding: 0 0 1.2rem 2.7rem; }
.construction li::before { content: "R." counter(result); position: absolute; left: 0; top: .18rem; color: var(--oxblood); font: .7rem var(--mono); }
.lemma { margin: 1.2rem 0 0 12rem; border-top: 1px dashed var(--rule); border-bottom: 1px dashed var(--rule); }
.lemma summary { padding: .8rem 0; color: var(--forest); font-size: .75rem; font-weight: 700; cursor: pointer; text-transform: uppercase; letter-spacing: .08em; }
.lemma summary span { margin-left: .6rem; color: #5e5e55; font-family: var(--serif); font-style: italic; font-weight: 400; letter-spacing: 0; text-transform: none; }
.lemma ul { display: flex; flex-wrap: wrap; gap: .45rem; margin: 0 0 1rem; padding: 0; list-style: none; }
.lemma li { padding: .23rem .55rem; border: 1px solid var(--rule); background: rgba(255,255,255,.25); font: .72rem var(--mono); }
.backlink { display: inline-block; margin: 1.3rem 0 0 12rem; font-size: .7rem; }

.skill-field { display: grid; grid-template-columns: repeat(3, 1fr); margin: 3rem 0 0; padding: 0; border-top: 1px solid var(--ink); list-style: none; }
.skill-field li { min-height: 7rem; display: flex; flex-direction: column; justify-content: space-between; padding: .8rem; border-right: 1px solid var(--rule); border-bottom: 1px solid var(--rule); font-size: 1rem; }
.skill-field li:nth-child(3n) { border-right: 0; }
.skill-field span { color: var(--oxblood); font: .65rem var(--mono); }
.credential-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 4rem; margin-top: 3rem; }
.credential-columns > div { border-top: 3px solid var(--forest); }
.credential-columns h3 { margin: .8rem 0 2rem; color: var(--forest); font: 700 .72rem var(--sans); letter-spacing: .12em; text-transform: uppercase; }
.credential-columns article { padding: 1rem 0; border-top: 1px solid var(--rule); }
.credential-columns article p { margin: 0; }
.credential-columns article p:first-child { font-size: 1.15rem; }
.credential-columns article p:last-child { color: #53544d; font-style: italic; }
.reviews { display: grid; grid-template-columns: 1fr 1fr; gap: 0; margin-top: 4rem; border-top: 1px solid var(--rule); border-left: 1px solid var(--rule); }
.reviews figure { margin: 0; padding: clamp(1.5rem, 3vw, 2.5rem); border-right: 1px solid var(--rule); border-bottom: 1px solid var(--rule); }
.reviews blockquote { margin: 0; }
.reviews blockquote p { margin-top: 0; }
.reviews blockquote p::before { content: "“"; color: var(--oxblood); font-size: 3rem; line-height: 0; vertical-align: -.35em; margin-right: .08em; }
.reviews figcaption { display: flex; flex-direction: column; margin-top: 1.5rem; font-family: var(--sans); font-size: .75rem; }
.reviews figcaption span { color: #5e5e55; }

body.compact .construction li:not(:first-child), body.compact .lemma, body.compact .backlink { display: none; }
body.compact .proposition { padding: 2.5rem 0; }
footer { display: flex; justify-content: space-between; padding: 2rem clamp(1.25rem, 5vw, 5rem); background: var(--forest); color: var(--paper); font-size: .75rem; }
footer p { margin: 0; text-transform: uppercase; letter-spacing: .1em; }
footer a { color: var(--paper); }

@media (max-width: 900px) {
  .masthead { min-height: auto; grid-template-columns: 3rem minmax(180px, 1fr) 1.4fr; padding: 2rem; }
  .journal-layout { grid-template-columns: 1fr; }
  .index { position: relative; height: auto; padding: 2rem 0; border-right: 0; border-bottom: 1px solid var(--ink); }
  .proof-index, .index__note { display: none; }
  .index nav:first-of-type ol { display: flex; flex-wrap: wrap; gap: .5rem 1.5rem; }
  .index nav:first-of-type li { border: 0; }
  .index nav:first-of-type li:last-child { border: 0; }
  .index nav:first-of-type a { padding: 0; }
  .index nav:first-of-type a::after { display: none; }
  .view-switch { max-width: 18rem; }
}
@media (max-width: 650px) {
  body { font-size: 16px; }
  .masthead { grid-template-columns: 2rem 1fr; align-items: start; gap: 1.2rem; }
  .masthead__mark { grid-row: span 2; }
  .masthead__portrait-wrap { max-width: 76vw; }
  .masthead__portrait { max-height: 55vh; }
  .masthead__copy { grid-column: 2; }
  h1 { font-size: clamp(3.2rem, 16vw, 5rem); }
  .proposition__header, .construction { grid-template-columns: 1fr; gap: .7rem; }
  .proposition__number { grid-row: auto; }
  .proposition::before { display: none; }
  .lemma, .backlink { margin-left: 0; }
  .skill-field { grid-template-columns: repeat(2, 1fr); }
  .skill-field li:nth-child(3n) { border-right: 1px solid var(--rule); }
  .skill-field li:nth-child(2n) { border-right: 0; }
  .credential-columns, .reviews { grid-template-columns: 1fr; gap: 2.5rem; }
  .reviews { gap: 0; }
  footer { align-items: flex-start; gap: 1rem; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
}