:root {
  color-scheme: light;
  --ink: #17232a;
  --navy: #20384a;
  --teal: #28766d;
  --rust: #965247;
  --ochre: #a47a36;
  --paper: #f4f1e8;
  --panel: #fffdf7;
  --muted: #637078;
  --line: #c9c5ba;
  --soft-blue: #e5ecee;
  --soft-teal: #dceae5;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--paper); color: var(--ink); }
a { color: inherit; text-underline-offset: 3px; }
.skip { position: absolute; left: -9999px; padding: .75rem 1rem; background: var(--navy); color: white; }
.skip:focus { left: 1rem; top: 1rem; z-index: 30; }
.masthead { position: sticky; top: 0; z-index: 20; display: flex; align-items: center; justify-content: space-between; min-height: 70px; padding: 0 max(24px, calc((100vw - 1200px) / 2)); background: rgba(244, 241, 232, .97); border-bottom: 1px solid var(--line); }
.brand { font: 700 1.03rem Georgia, serif; text-decoration: none; }
.brand span { margin-left: .35rem; color: var(--rust); font: 800 .61rem ui-monospace, monospace; }
nav { display: flex; gap: 1.5rem; font-size: .74rem; font-weight: 700; }
nav a { text-decoration: none; }

.hero { display: grid; grid-template-columns: 1.02fr .98fr; gap: 5rem; align-items: center; max-width: 1200px; margin: auto; padding: 86px 24px 72px; }
.kicker { margin: 0; color: var(--rust); font: 800 .66rem/1.5 ui-monospace, SFMono-Regular, Consolas, monospace; letter-spacing: .12em; text-transform: uppercase; }
h1, h2, h3 { font-family: Georgia, "Times New Roman", serif; letter-spacing: -.028em; }
h1 { max-width: 690px; margin: 1rem 0 1.5rem; font-size: clamp(3.2rem, 6.4vw, 5.6rem); line-height: .95; font-weight: 650; }
.abstract { max-width: 690px; color: var(--muted); font-size: 1.06rem; line-height: 1.75; }
.actions { display: flex; flex-wrap: wrap; gap: .75rem; margin: 2rem 0 1rem; }
.button { display: inline-flex; min-height: 44px; align-items: center; justify-content: center; padding: .75rem 1rem; border: 1px solid var(--navy); font-size: .75rem; font-weight: 800; text-decoration: none; }
.button.primary { background: var(--navy); color: white; }
.note { color: var(--muted); font-size: .7rem; }

.decision-figure { margin: 0; background: var(--panel); border: 1px solid var(--line); border-top: 6px solid var(--navy); box-shadow: 0 20px 55px rgba(23, 35, 42, .09); }
.decision-figure figcaption { padding: .7rem 1rem; border-bottom: 1px solid var(--line); color: var(--muted); font: .62rem ui-monospace, monospace; text-transform: uppercase; }
.question { padding: 1rem; background: var(--soft-blue); }
.question span, .reveal span { display: block; color: var(--rust); font: 800 .6rem ui-monospace, monospace; text-transform: uppercase; }
.question strong { display: block; margin-top: .35rem; font: 650 1rem/1.45 Georgia, serif; }
.anonymous-pair { display: grid; grid-template-columns: 1fr 48px 1fr; align-items: center; padding: 1rem; }
.anonymous-pair article { min-height: 170px; padding: 1rem; border: 1px solid var(--line); background: white; }
.anonymous-pair small { color: var(--muted); font: .6rem ui-monospace, monospace; text-transform: uppercase; }
.anonymous-pair h2 { margin: .45rem 0 1.1rem; color: var(--teal); font-size: 1.35rem; }
.anonymous-pair i { display: block; height: 7px; margin: .65rem 0; background: #dad9d3; }
.anonymous-pair i:nth-of-type(2) { width: 82%; }
.anonymous-pair i:nth-of-type(3) { width: 92%; }
.anonymous-pair > b { color: var(--rust); font: italic 700 .68rem Georgia, serif; text-align: center; }
.reveal { margin: 0 1rem 1rem; padding: 1rem; border: 1px solid #d5c18e; border-top: 4px solid var(--ochre); background: #f4eddb; }
.reveal strong { display: block; margin: .45rem 0 .3rem; font: 650 1.25rem Georgia, serif; }
.reveal small { color: #6f6040; font-size: .65rem; }

.proof-strip { display: grid; grid-template-columns: repeat(5, 1fr); max-width: 1200px; margin: auto; border: 1px solid var(--line); background: var(--panel); }
.proof-strip div { padding: 1.3rem 1rem; border-right: 1px solid var(--line); text-align: center; }
.proof-strip div:last-child { border-right: 0; }
.proof-strip strong { display: block; color: var(--navy); font: 650 1.6rem Georgia, serif; }
.proof-strip span { color: var(--muted); font-size: .63rem; }

.section { max-width: 1200px; margin: auto; padding: 104px 24px; }
.section-head { display: grid; grid-template-columns: 1fr 1fr; column-gap: 5rem; align-items: end; margin-bottom: 2.6rem; }
.section-head .kicker { grid-column: 1 / -1; }
.section-head h2 { margin: .8rem 0 0; font-size: clamp(2.35rem, 4.5vw, 4rem); line-height: 1.02; font-weight: 650; }
.section-head > p:last-child { margin: 0; color: var(--muted); font-size: .85rem; line-height: 1.7; }
.mode-grid { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 3px solid var(--navy); }
.mode-grid article { min-height: 310px; padding: 1.4rem; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--panel); }
.mode-grid article:last-child { border-right: 0; }
.mode-grid article > span { color: var(--teal); font: 800 .68rem ui-monospace, monospace; }
.mode-grid .kicker { margin-top: 2rem; }
.mode-grid h3 { margin: .65rem 0 .85rem; font-size: 1.5rem; line-height: 1.2; }
.mode-grid article > p:not(.kicker) { color: var(--muted); font-size: .79rem; line-height: 1.65; }
.mode-grid a { display: inline-block; margin-top: 1rem; color: var(--navy); font-size: .72rem; font-weight: 800; }

.arena { background: #e7e4dc; border-block: 1px solid var(--line); }
.arena .inner { padding-block: 90px; }
.comparison-table { border: 1px solid var(--line); background: var(--panel); }
.comparison-row { display: grid; grid-template-columns: 1.5fr .75fr .9fr; border-bottom: 1px solid var(--line); }
.comparison-row:last-child { border-bottom: 0; }
.comparison-row > * { padding: .9rem 1rem; border-right: 1px solid var(--line); font-size: .74rem; }
.comparison-row > *:last-child { border-right: 0; }
.comparison-row.heading { color: white; background: var(--navy); }
.comparison-row strong { color: var(--teal); }

.method-grid { display: grid; grid-template-columns: repeat(3, 1fr); margin: 0; padding: 0; border-top: 3px solid var(--navy); list-style: none; }
.method-grid li { min-height: 205px; padding: 1.35rem; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--panel); }
.method-grid li:nth-child(3n) { border-right: 0; }
.method-grid b { color: var(--rust); font: 800 .66rem ui-monospace, monospace; }
.method-grid h3 { margin: 1.15rem 0 .65rem; font-size: 1.18rem; }
.method-grid p { margin: 0; color: var(--muted); font-size: .78rem; line-height: 1.6; }
.study-links { display: flex; flex-wrap: wrap; gap: 1.3rem; margin-top: 1.2rem; font-size: .72rem; font-weight: 800; }
.disclosure { margin: 1rem 0 0; color: var(--muted); font-size: .68rem; }
.installation pre { margin: 0; padding: 1.4rem; overflow: auto; border-left: 6px solid var(--rust); background: var(--navy); color: #f7f3e9; font: .76rem/1.8 ui-monospace, Consolas, monospace; }
.limit-grid { display: grid; grid-template-columns: repeat(2, 1fr); border: 1px solid var(--line); }
.limit-grid p { margin: 0; padding: 1.4rem; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--panel); color: var(--muted); font-size: .8rem; line-height: 1.6; }
.limit-grid p:nth-child(2n) { border-right: 0; }
.limit-grid p:nth-last-child(-n + 2) { border-bottom: 0; }
.limit-grid b { color: var(--ink); }
footer { display: flex; justify-content: space-between; gap: 2rem; padding: 2.2rem max(24px, calc((100vw - 1200px) / 2)); color: #d9e1e4; background: var(--navy); font-size: .67rem; }

@media (max-width: 880px) {
  .hero, .section-head { grid-template-columns: 1fr; }
  .hero { gap: 3rem; }
  .section-head > p:last-child { margin-top: 1rem; }
  .mode-grid, .method-grid { grid-template-columns: repeat(2, 1fr); }
  .mode-grid article:nth-child(2), .method-grid li:nth-child(2n) { border-right: 0; }
  .mode-grid article:last-child { border-right: 1px solid var(--line); }
  .proof-strip { grid-template-columns: repeat(3, 1fr); }
}

@media (max-width: 600px) {
  nav a:not(:last-child) { display: none; }
  h1 { font-size: 3.15rem; }
  .hero { padding-top: 54px; }
  .anonymous-pair { grid-template-columns: 1fr; gap: .65rem; }
  .anonymous-pair > b { min-height: 20px; }
  .proof-strip, .mode-grid, .method-grid, .limit-grid { grid-template-columns: 1fr; }
  .proof-strip div, .mode-grid article, .method-grid li, .limit-grid p { border-right: 0 !important; border-bottom: 1px solid var(--line) !important; }
  .proof-strip div:last-child, .mode-grid article:last-child, .method-grid li:last-child, .limit-grid p:last-child { border-bottom: 0 !important; }
  .comparison-row { grid-template-columns: 1.3fr .8fr .9fr; }
  .comparison-row > * { padding: .7rem .55rem; font-size: .62rem; }
  footer { flex-direction: column; }
}

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