:root {
  --ink: #071116;
  --ink-soft: #17313a;
  --paper: #f1ede3;
  --paper-deep: #e6dfd0;
  --mist: #d5e1dd;
  --blue: #2c6472;
  --blue-bright: #5aa9b5;
  --red: #de5c50;
  --red-deep: #a53b36;
  --gold: #d4a84e;
  --line: rgba(7, 17, 22, .18);
  --line-light: rgba(241, 237, 227, .2);
  --serif: Iowan Old Style, Baskerville, Palatino Linotype, Book Antiqua, Georgia, serif;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --shell: min(1180px, calc(100vw - 64px));
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  text-rendering: optimizeLegibility;
}
body::before {
  position: fixed;
  z-index: -1;
  inset: 0;
  opacity: .24;
  pointer-events: none;
  content: "";
  background-image: linear-gradient(rgba(7,17,22,.04) 1px, transparent 1px), linear-gradient(90deg, rgba(7,17,22,.04) 1px, transparent 1px);
  background-size: 32px 32px;
  mask-image: linear-gradient(to bottom, black, transparent 62%);
}
body#top:focus { outline: none; }

a { color: inherit; }
button, input { font: inherit; }
button { cursor: pointer; }
button:focus-visible, a:focus-visible, input:focus-visible, summary:focus-visible {
  outline: 3px solid var(--gold);
  outline-offset: 4px;
}
.skip-link {
  position: fixed;
  z-index: 20;
  top: -5rem;
  left: 1rem;
  padding: .6rem .9rem;
  color: var(--paper);
  background: var(--ink);
}
.skip-link:focus { top: 1rem; }
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.site-header {
  display: flex;
  width: var(--shell);
  margin: 0 auto;
  padding: 28px 0 18px;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
}
.brand, .language-link { text-decoration: none; }
.brand { display: inline-flex; gap: 12px; align-items: center; }
.brand-mark {
  display: inline-flex;
  width: 42px;
  height: 42px;
  align-items: center;
  justify-content: center;
  color: var(--paper);
  background: var(--ink);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: -.12em;
}
.brand-mark span { color: var(--red); }
.brand-text {
  max-width: 14rem;
  font-size: .7rem;
  font-weight: 700;
  letter-spacing: .13em;
  line-height: 1.2;
  text-transform: uppercase;
}
.language-link {
  border-bottom: 1px solid var(--ink);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.section-shell { width: var(--shell); margin: 0 auto; }
.hero {
  display: grid;
  min-height: 680px;
  padding: 82px 0 100px;
  align-items: center;
  grid-template-columns: minmax(0, .98fr) minmax(380px, .82fr);
  gap: clamp(40px, 8vw, 120px);
}
.eyebrow {
  margin: 0 0 24px;
  color: var(--red-deep);
  font-family: var(--mono);
  font-size: .69rem;
  font-weight: 700;
  letter-spacing: .16em;
  line-height: 1.4;
  text-transform: uppercase;
}
h1, h2, h3, p { margin-top: 0; }
h1, h2 {
  font-family: var(--serif);
  font-weight: 400;
  letter-spacing: -.045em;
}
h1 {
  max-width: 9ch;
  margin-bottom: 28px;
  font-size: clamp(4rem, 9vw, 8.6rem);
  line-height: .86;
}
h2 {
  max-width: 13ch;
  margin-bottom: 26px;
  font-size: clamp(2.65rem, 5.4vw, 5.2rem);
  line-height: .94;
}
.hero-lead, .lede {
  max-width: 38rem;
  font-size: clamp(1.05rem, 1.55vw, 1.3rem);
  line-height: 1.55;
}
.hero-lead { margin-bottom: 32px; }
.hero-note {
  display: flex;
  max-width: 27rem;
  margin-bottom: 0;
  align-items: center;
  gap: 10px;
  color: var(--blue);
  font-family: var(--mono);
  font-size: .75rem;
  line-height: 1.5;
}
.note-dot { width: 8px; height: 8px; flex: 0 0 auto; border-radius: 50%; background: var(--red); }

.hero-instrument { margin: 0; }
.compass-face {
  --compass-size: min(43vw, 500px);
  position: relative;
  width: var(--compass-size);
  height: var(--compass-size);
  max-width: 100%;
  margin: 0 auto;
  overflow: hidden;
  border: 1px solid rgba(241,237,227,.35);
  border-radius: 50%;
  background: var(--ink);
  box-shadow: 22px 24px 0 var(--paper-deep), 0 0 0 14px rgba(7,17,22,.045);
}
.compass-face::before, .compass-face::after {
  position: absolute;
  inset: 8%;
  border: 1px solid rgba(241,237,227,.14);
  border-radius: 50%;
  content: "";
}
.compass-face::after { inset: 20%; border-color: rgba(241,237,227,.08); }
.compass-grid {
  position: absolute;
  inset: 0;
  opacity: .45;
  background: repeating-conic-gradient(from -1deg, rgba(241,237,227,.56) 0deg 1deg, transparent 1deg 15deg);
  mask-image: radial-gradient(circle, transparent 0 56%, black 56.5% 62%, transparent 62.5% 100%);
}
.compass-crosshair { position: absolute; inset: 8%; opacity: .14; background: linear-gradient(90deg, transparent 49.8%, var(--paper) 50%, transparent 50.2%), linear-gradient(0deg, transparent 49.8%, var(--paper) 50%, transparent 50.2%); }
.compass-cardinal { position: absolute; z-index: 2; color: var(--paper); font-family: var(--mono); font-size: .68rem; font-weight: 700; }
.cardinal-n { top: 9%; left: 50%; color: var(--red); transform: translateX(-50%); }
.cardinal-e { top: 50%; right: 9%; transform: translateY(-50%); }
.cardinal-s { bottom: 9%; left: 50%; transform: translateX(-50%); }
.cardinal-w { top: 50%; left: 9%; transform: translateY(-50%); }
.compass-needle { position: absolute; z-index: 3; top: 17%; left: 50%; width: 3px; height: 33%; transform: translateX(-50%) rotate(var(--compass-angle, 0deg)); transform-origin: 50% 100%; transition: transform 480ms cubic-bezier(.2,.8,.2,1); }
.compass-needle::before, .compass-needle::after { position: absolute; left: -5px; width: 13px; height: 50%; content: ""; clip-path: polygon(50% 0, 100% 100%, 50% 86%, 0 100%); }
.compass-needle::before { top: 0; background: currentColor; }
.compass-needle::after { bottom: 0; transform: rotate(180deg); background: rgba(241,237,227,.25); }
.needle-true { color: var(--blue-bright); }
.needle-magnetic { color: var(--red); }
.compass-hub { position: absolute; z-index: 5; top: 50%; left: 50%; width: 18px; height: 18px; border: 4px solid var(--paper); border-radius: 50%; background: var(--red); transform: translate(-50%, -50%); }
.compass-degree { position: absolute; z-index: 5; bottom: 14%; left: 50%; color: var(--paper); font-family: var(--mono); font-size: clamp(.8rem, 1.6vw, 1.1rem); letter-spacing: .08em; transform: translateX(-50%); }
.hero-instrument figcaption { display: flex; margin: 28px auto 0; justify-content: center; gap: 16px; color: var(--ink-soft); font-size: .7rem; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; }
.legend-line { width: 22px; height: 2px; margin-right: -10px; align-self: center; }
.legend-blue { background: var(--blue); }
.legend-red { background: var(--red); }

.statement-band { color: var(--paper); background: var(--ink); }
.statement-inner { display: grid; padding: 42px 0 46px; grid-template-columns: 80px minmax(0, 1fr); align-items: start; gap: 30px; }
.statement-index { color: var(--red); font-family: var(--mono); font-size: .72rem; font-weight: 700; letter-spacing: .15em; }
.statement-inner p { max-width: 50rem; margin: 0; font-family: var(--serif); font-size: clamp(1.7rem, 3.2vw, 3.4rem); letter-spacing: -.03em; line-height: 1.04; }

.chapter { padding-top: 150px; padding-bottom: 150px; }
.chapter-split, .why-section { display: grid; grid-template-columns: minmax(0, .95fr) minmax(300px, .8fr); align-items: center; gap: clamp(50px, 10vw, 150px); }
.chapter-copy > p:last-child { max-width: 32rem; margin-top: 30px; color: var(--blue); font-size: .95rem; }
.two-norths-figure { margin: 0; }
.north-diagram { position: relative; width: min(100%, 430px); aspect-ratio: 1; margin: 0 auto 26px; border: 1px solid var(--line); border-radius: 50%; background: radial-gradient(circle, rgba(90,169,181,.12) 0 2px, transparent 2.5px 30%, rgba(222,92,80,.08) 30.5% 31%, transparent 31.5% 100%); }
.north-diagram::before { position: absolute; inset: 8%; border: 1px dashed var(--line); border-radius: 50%; content: ""; }
.diagram-origin { position: absolute; z-index: 3; top: 50%; left: 50%; width: 12px; height: 12px; border: 3px solid var(--paper); border-radius: 50%; background: var(--ink); transform: translate(-50%, -50%); }
.diagram-line { position: absolute; top: 14%; left: calc(50% - 1px); width: 2px; height: 36%; transform-origin: 50% 100%; }
.diagram-line::before { position: absolute; top: -7px; left: -5px; width: 12px; height: 12px; border-radius: 50%; content: ""; }
.diagram-line span { position: absolute; top: -38px; left: 15px; white-space: nowrap; font-family: var(--mono); font-size: .68rem; letter-spacing: .1em; text-transform: uppercase; }
.diagram-true { color: var(--blue); background: var(--blue); }
.diagram-true::before { background: var(--blue); }
.diagram-magnetic { color: var(--red); background: var(--red); transform: rotate(15deg); }
.diagram-magnetic::before { background: var(--red); }
.diagram-arc { position: absolute; top: 29%; left: 48%; width: 50px; height: 50px; border: 1px solid var(--gold); border-right-color: transparent; border-bottom-color: transparent; border-radius: 50%; transform: rotate(15deg); }
.diagram-arc span { position: absolute; top: -17px; left: 4px; color: var(--gold); font-family: var(--serif); font-size: 1.4rem; transform: rotate(-15deg); }
.two-norths-figure figcaption { max-width: 19rem; margin-left: auto; color: var(--blue); font-size: .8rem; }

.explorer-section { padding: 138px 0 160px; color: var(--paper); background: var(--ink); }
.explorer-section .eyebrow { color: var(--red); }
.explorer-section h2 { max-width: 10ch; }
.explorer-section .lede { color: rgba(241,237,227,.74); }
.wide-heading { max-width: 720px; }
.explorer-panel { margin-top: 65px; border-top: 1px solid var(--line-light); border-bottom: 1px solid var(--line-light); }
.explorer-controls { display: grid; padding: 32px 0; grid-template-columns: 1.2fr 1fr; gap: 50px; border-bottom: 1px solid var(--line-light); }
.control-label { display: flex; margin-bottom: 16px; justify-content: space-between; color: var(--paper); font-family: var(--mono); font-size: .7rem; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; }
.place-list { display: flex; flex-wrap: wrap; gap: 9px; }
.place-button { padding: .6rem .8rem; border: 1px solid rgba(241,237,227,.35); border-radius: 0; color: var(--paper); background: transparent; font-size: .86rem; transition: color 180ms ease, background 180ms ease, border-color 180ms ease; }
.place-button:hover, .place-button.is-active { border-color: var(--red); color: var(--ink); background: var(--red); }
input[type="range"] { width: 100%; height: 4px; accent-color: var(--red); cursor: ew-resize; }
.range-ends { display: flex; justify-content: space-between; color: rgba(241,237,227,.45); font-family: var(--mono); font-size: .65rem; }
.year-control output { color: var(--red); }
.explorer-reading { display: grid; padding: 44px 0 36px; grid-template-columns: 1fr 1fr 1fr; gap: 30px; align-items: center; }
.reading-compass { display: flex; align-items: center; gap: 17px; }
.mini-compass { position: relative; width: 70px; height: 70px; flex: 0 0 auto; border: 1px solid rgba(241,237,227,.5); border-radius: 50%; background: repeating-conic-gradient(from 0deg, rgba(241,237,227,.4) 0deg 1deg, transparent 1deg 30deg); }
.mini-compass span { position: absolute; top: 17px; left: 50%; width: 2px; height: 18px; transform-origin: 50% 100%; transform: translateX(-50%) rotate(var(--mini-angle, 0deg)); }
.mini-true { background: var(--blue-bright); }
.mini-magnetic { background: var(--red); }
.mini-compass i { position: absolute; top: 50%; left: 50%; width: 8px; height: 8px; border: 2px solid var(--paper); border-radius: 50%; background: var(--red); transform: translate(-50%, -50%); }
.reading-place, .reading-date { display: block; }
.reading-place { font-family: var(--serif); font-size: 1.4rem; }
.reading-date { color: rgba(241,237,227,.55); font-family: var(--mono); font-size: .7rem; }
.reading-number { padding-left: 25px; border-left: 1px solid var(--line-light); }
.reading-number span, .reading-correction span { display: block; color: rgba(241,237,227,.55); font-family: var(--mono); font-size: .66rem; letter-spacing: .1em; text-transform: uppercase; }
.reading-number strong { display: block; margin: 3px 0 2px; color: var(--red); font-family: var(--serif); font-size: clamp(2.8rem, 5vw, 5rem); font-weight: 400; letter-spacing: -.06em; line-height: .9; }
.reading-correction { padding-left: 25px; border-left: 1px solid var(--line-light); }
.reading-correction strong { display: block; margin: 3px 0 7px; color: var(--blue-bright); font-family: var(--mono); font-size: 1.4rem; }
.reading-correction small { display: block; max-width: 14rem; color: rgba(241,237,227,.58); font-size: .76rem; line-height: 1.45; }
.model-note { margin: 0; padding: 0 0 27px; color: rgba(241,237,227,.55); font-family: var(--mono); font-size: .66rem; }

.drift-section { padding-bottom: 170px; }
.drift-section .section-heading { max-width: 650px; }
.drift-lab { display: grid; margin-top: 65px; padding: 36px 0 44px; grid-template-columns: minmax(240px, .7fr) 1fr; gap: clamp(40px, 8vw, 120px); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); align-items: center; }
.drift-controls { max-width: 330px; }
.drift-controls .control-label { color: var(--ink); }
.drift-controls output { color: var(--red-deep); }
.drift-controls input[type="range"] { accent-color: var(--blue); }
.drift-controls .range-ends { color: rgba(7,17,22,.48); }
.formula-note { margin: 30px 0 0; color: var(--blue); font-family: var(--mono); font-size: .68rem; line-height: 1.5; }
.drift-visual { min-width: 0; }
.drift-axis { position: relative; height: 160px; }
.drift-track { position: absolute; top: 78px; right: 4%; left: 8%; height: 1px; background: var(--line); }
.drift-track::before, .drift-track::after { position: absolute; top: -4px; width: 9px; height: 9px; border-radius: 50%; content: ""; }
.drift-track::before { left: -4px; background: var(--ink); }
.drift-track::after { right: -4px; background: var(--blue); }
.drift-start, .drift-destination { position: absolute; z-index: 2; top: 78px; width: 12px; height: 12px; border-radius: 50%; transform: translate(-50%, -50%); }
.drift-start { left: 8%; background: var(--ink); }
.drift-destination { left: calc(8% + var(--drift-progress, 25%) * .88); background: var(--red); box-shadow: 0 0 0 6px rgba(222,92,80,.14); transition: left 300ms ease; }
.drift-destination::before { position: absolute; bottom: 11px; left: 50%; width: 1px; height: 44px; background: var(--red); content: ""; transform: translateX(-50%); }
.drift-values { display: flex; justify-content: space-between; align-items: end; gap: 20px; }
.drift-values strong { color: var(--red-deep); font-family: var(--serif); font-size: clamp(2.8rem, 6vw, 5.8rem); font-weight: 400; letter-spacing: -.07em; line-height: .85; }
.drift-values span { max-width: 10rem; color: var(--blue); font-family: var(--mono); font-size: .67rem; line-height: 1.4; text-align: right; text-transform: uppercase; }
.callout { max-width: 38rem; margin: 34px 0 0 auto; padding-left: 25px; border-left: 3px solid var(--red); color: var(--blue); font-family: var(--serif); font-size: 1.35rem; line-height: 1.2; }

.timeline-section { padding: 135px 0 155px; color: var(--paper); background: var(--blue); }
.timeline-section .eyebrow { color: var(--gold); }
.timeline-section .lede { color: rgba(241,237,227,.78); }
.timeline-figure { margin: 66px 0 0; padding: 30px 0 0; border-top: 1px solid rgba(241,237,227,.36); }
.timeline-meta { display: flex; justify-content: space-between; gap: 20px; color: rgba(241,237,227,.74); font-family: var(--mono); font-size: .7rem; letter-spacing: .07em; text-transform: uppercase; }
.timeline-meta strong { color: var(--paper); font-weight: 700; }
.timeline-scale-note { margin: 12px 0 0; color: rgba(241,237,227,.56); font-family: var(--mono); font-size: .66rem; line-height: 1.45; }
.timeline-svg { display: block; width: 100%; height: auto; margin-top: 20px; overflow: visible; }
.timeline-grid line { stroke: rgba(241,237,227,.18); stroke-width: 1; }
.timeline-midline { stroke: rgba(241,237,227,.5); stroke-width: 1; stroke-dasharray: 4 6; }
.timeline-line { fill: none; stroke: var(--red); stroke-width: 5; stroke-linecap: round; }
.timeline-dot { fill: var(--gold); stroke: var(--paper); stroke-width: 3; }
.timeline-svg text { fill: rgba(241,237,227,.75); font-family: var(--mono); font-size: 14px; }
.timeline-svg .axis-label { fill: var(--paper); font-size: 12px; letter-spacing: .12em; }
.timeline-svg .axis-bottom { transform: translateY(35px); }
.timeline-figure figcaption { margin-top: -6px; color: rgba(241,237,227,.7); font-family: var(--mono); font-size: .7rem; text-transform: uppercase; }
.timeline-value { color: var(--gold); font-size: 1rem; }

.why-section { padding-top: 150px; padding-bottom: 150px; align-items: start; }
.facts-list { border-top: 1px solid var(--line); }
.fact-row { display: grid; padding: 26px 0; grid-template-columns: 115px 1fr; gap: 24px; border-bottom: 1px solid var(--line); }
.fact-row strong { color: var(--red-deep); font-family: var(--serif); font-size: 2.3rem; font-weight: 400; letter-spacing: -.05em; line-height: 1; }
.fact-row span { color: var(--blue); font-size: .92rem; line-height: 1.45; }

.method-section { color: var(--paper); background: var(--ink-soft); }
.method-grid { display: grid; padding: 105px 0 115px; grid-template-columns: .8fr 1fr; gap: clamp(50px, 10vw, 150px); }
.method-section .eyebrow { color: var(--red); }
.method-section h2 { max-width: 10ch; }
.method-grid p { max-width: 37rem; color: rgba(241,237,227,.78); }
details { max-width: 37rem; margin-top: 34px; border-top: 1px solid var(--line-light); border-bottom: 1px solid var(--line-light); }
summary { padding: 19px 0; color: var(--paper); cursor: pointer; font-family: var(--mono); font-size: .72rem; font-weight: 700; letter-spacing: .1em; list-style-position: inside; text-transform: uppercase; }
details p { margin: 0 0 20px; font-size: .84rem; }
details ul { margin: 0 0 26px; padding-left: 1.1rem; color: rgba(241,237,227,.7); font-size: .8rem; }
details li + li { margin-top: 8px; }
details a { color: var(--blue-bright); }

.site-footer { display: flex; min-height: 150px; padding: 38px 0 42px; align-items: center; justify-content: space-between; gap: 30px; }
.site-footer > div:first-child { display: flex; align-items: center; gap: 17px; }
.footer-mark { width: 36px; height: 36px; }
.site-footer p { max-width: 17rem; margin: 0; color: var(--blue); font-family: var(--serif); font-size: 1rem; line-height: 1.15; }
.footer-meta { display: flex; align-items: center; gap: 25px; color: var(--blue); font-family: var(--mono); font-size: .67rem; text-transform: uppercase; }
.footer-meta a { color: var(--red-deep); text-decoration: none; }
.back-to-top { display: inline-flex; min-width: 44px; min-height: 44px; align-items: center; justify-content: center; }
.back-to-top.js-back-to-top { position: fixed; z-index: 10; right: max(14px, calc((100vw - var(--shell)) / 2)); bottom: var(--back-to-top-bottom, 16px); padding: 0 12px; color: var(--paper); background: var(--red-deep); opacity: 0; visibility: hidden; pointer-events: none; transition: opacity 180ms ease, visibility 180ms ease; }
.back-to-top.js-back-to-top.is-visible { opacity: 1; visibility: visible; pointer-events: auto; }

@media (max-width: 820px) {
  :root { --shell: min(100% - 36px, 650px); }
  .site-header { padding-top: 18px; }
  .brand-text { max-width: 9rem; font-size: .62rem; }
  .hero { min-height: auto; padding: 70px 0 90px; grid-template-columns: 1fr; gap: 62px; }
  h1 { max-width: 8ch; font-size: clamp(4rem, 17vw, 6.5rem); }
  .compass-face { --compass-size: min(82vw, 460px); }
  .hero-instrument figcaption { flex-wrap: wrap; }
  .statement-inner { grid-template-columns: 1fr; gap: 14px; }
  .chapter { padding-top: 100px; padding-bottom: 100px; }
  .chapter-split, .why-section { grid-template-columns: 1fr; gap: 55px; }
  .two-norths-figure { max-width: 440px; }
  .explorer-section { padding: 100px 0 110px; }
  .explorer-controls, .explorer-reading { grid-template-columns: 1fr; gap: 32px; }
  .explorer-reading { padding: 38px 0 25px; }
  .reading-number, .reading-correction { padding-top: 24px; padding-left: 0; border-top: 1px solid var(--line-light); border-left: 0; }
  .drift-section { padding-bottom: 110px; }
  .drift-lab { grid-template-columns: 1fr; gap: 50px; }
  .drift-controls { max-width: none; }
  .timeline-section { padding: 100px 0 115px; }
  .timeline-figure { overflow-x: auto; }
  .timeline-svg { min-width: 690px; }
  .method-grid { grid-template-columns: 1fr; gap: 44px; }
}

@media (max-width: 500px) {
  :root { --shell: calc(100% - 28px); }
  .brand-text { display: none; }
  .hero { padding-top: 55px; }
  h2 { font-size: clamp(2.55rem, 13vw, 4rem); }
  .compass-face { box-shadow: 10px 12px 0 var(--paper-deep), 0 0 0 8px rgba(7,17,22,.045); }
  .chapter-copy > p:last-child { font-size: .86rem; }
  .fact-row { grid-template-columns: 85px 1fr; gap: 14px; }
  .fact-row strong { font-size: 1.9rem; }
  .site-footer { display: block; padding-bottom: 34px; }
  .footer-meta { margin-top: 25px; justify-content: space-between; }
  .back-to-top.js-back-to-top { right: 14px; bottom: var(--back-to-top-bottom, 14px); }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
}