:root {
  --paper: #f3f0e9;
  --paper-bright: #fbfaf6;
  --ink: #151819;
  --ink-soft: #555b5c;
  --graphite: #11171a;
  --blue: #246bfe;
  --blue-dark: #1746ad;
  --blue-pale: #dbe6ff;
  --line: rgba(21, 24, 25, 0.16);
  --serif: Iowan Old Style, Baskerville, "Times New Roman", serif;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --content: 760px;
  --wide: 1240px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; background: var(--paper); }
body { margin: 0; color: var(--ink); font-family: var(--sans); background: var(--paper); }
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 0.18em; }
button, input { font: inherit; }
img, svg { display: block; max-width: 100%; }
::selection { color: white; background: var(--blue); }

.skip-link { position: fixed; z-index: 100; top: 0.75rem; left: 0.75rem; padding: 0.7rem 1rem; color: white; background: var(--ink); transform: translateY(-150%); }
.skip-link:focus { transform: none; }
.reading-progress { position: fixed; z-index: 90; top: 0; right: 0; left: 0; height: 3px; pointer-events: none; background: linear-gradient(90deg, var(--blue) var(--reading-progress, 0%), transparent 0); }
.archive-shell { width: min(calc(100% - 2rem), var(--wide)); margin-inline: auto; }

.archive-header { position: relative; z-index: 30; border-bottom: 1px solid var(--line); background: color-mix(in srgb, var(--paper) 91%, transparent); backdrop-filter: blur(14px); }
.archive-header__inner { display: flex; min-height: 72px; align-items: center; justify-content: space-between; gap: 2rem; }
.archive-brand { display: inline-flex; align-items: center; gap: 0.75rem; font-size: 0.78rem; font-weight: 760; letter-spacing: 0.08em; text-decoration: none; text-transform: uppercase; }
.archive-brand__mark { display: grid; width: 28px; aspect-ratio: 1; place-items: center; color: white; background: var(--ink); }
.archive-nav { display: flex; align-items: center; gap: clamp(1rem, 3vw, 2.2rem); }
.archive-nav a { color: var(--ink-soft); font-size: 0.76rem; font-weight: 680; text-decoration: none; }
.archive-nav a:hover, .archive-nav a[aria-current="page"] { color: var(--blue); }

.article-hero { position: relative; overflow: hidden; min-height: min(880px, calc(100svh - 72px)); color: white; background: var(--graphite); }
.article-hero::before { position: absolute; inset: 0; content: ""; opacity: 0.55; background-image: linear-gradient(rgba(255,255,255,.06) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.06) 1px, transparent 1px); background-size: 48px 48px; mask-image: linear-gradient(to bottom, black, transparent 78%); }
.article-hero__inner { position: relative; display: grid; min-height: inherit; align-items: center; grid-template-columns: minmax(0, 1.08fr) minmax(360px, 0.92fr); gap: clamp(2rem, 6vw, 7rem); padding-block: clamp(5rem, 10vw, 9rem); }
.kicker { display: flex; align-items: center; gap: 0.75rem; margin: 0 0 2rem; color: #a9c4ff; font: 700 0.7rem/1.4 var(--mono); letter-spacing: 0.11em; text-transform: uppercase; }
.kicker::before { width: 2.5rem; height: 1px; content: ""; background: currentColor; }
.article-hero h1 { max-width: 13ch; margin: 0; font-family: var(--serif); font-size: clamp(3.35rem, 7.4vw, 7.3rem); font-weight: 500; line-height: 0.91; letter-spacing: -0.065em; }
.article-hero__lede { max-width: 54ch; margin: 2rem 0; color: #cad0d2; font-size: clamp(1rem, 1.7vw, 1.22rem); line-height: 1.65; }
.article-meta { display: flex; flex-wrap: wrap; gap: 0.7rem 1.5rem; margin: 0; padding: 0; color: #aeb7ba; font: 650 0.67rem/1.4 var(--mono); list-style: none; }
.article-meta strong { color: white; font-weight: inherit; }

.hero-asset { position: relative; overflow: hidden; aspect-ratio: 4 / 5; margin: 0; border: 1px solid rgba(255,255,255,.18); background: #07101b; box-shadow: 0 35px 80px rgba(0,0,0,.38); }
.hero-asset img { width: 100%; height: 112%; object-fit: cover; object-position: 67% center; transform: translate3d(0, var(--asset-y, 0), 0) scale(var(--asset-scale, 1.05)); will-change: transform; }
.hero-asset::after { position: absolute; inset: 0; content: ""; pointer-events: none; background: linear-gradient(110deg, transparent 40%, rgba(120,172,255,.15) 49%, transparent 58%); transform: translateX(-110%); animation: asset-sheen 5.8s ease-in-out infinite 1s; }
.hero-asset figcaption { position: absolute; right: 1rem; bottom: 1rem; left: 1rem; padding-top: .75rem; border-top: 1px solid rgba(255,255,255,.35); color: #d5def0; font: 650 .62rem/1.45 var(--mono); text-transform: uppercase; }

.article-section { padding-block: clamp(5rem, 10vw, 9rem); }
.article-copy { width: min(calc(100% - 2rem), var(--content)); margin-inline: auto; }
.article-copy--wide { width: min(calc(100% - 2rem), var(--wide)); }
.section-number { margin: 0 0 1.4rem; color: var(--blue); font: 700 0.67rem/1.4 var(--mono); letter-spacing: 0.12em; text-transform: uppercase; }
.article-copy h2 { max-width: 18ch; margin: 0 0 2rem; font-family: var(--serif); font-size: clamp(2.4rem, 5vw, 4.7rem); font-weight: 500; line-height: 1; letter-spacing: -0.052em; }
.article-copy h3 { margin: 3.5rem 0 1rem; font-size: clamp(1.4rem, 2.4vw, 2rem); line-height: 1.2; letter-spacing: -0.035em; }
.article-copy p, .article-copy li { color: #2f3435; font-family: var(--serif); font-size: clamp(1.1rem, 1.55vw, 1.27rem); line-height: 1.75; }
.article-copy p { margin: 0 0 1.45em; }
.article-copy strong { color: var(--ink); }
.article-copy sup a { color: var(--blue-dark); font: 750 0.62rem var(--sans); text-decoration: none; }
.lead { color: var(--ink) !important; font-size: clamp(1.35rem, 2.5vw, 1.9rem) !important; line-height: 1.5 !important; }
.pull-quote { margin: 4.5rem 0; padding: 1rem 0 1rem clamp(1.5rem, 5vw, 4rem); border-left: 4px solid var(--blue); font-family: var(--serif); font-size: clamp(1.8rem, 4vw, 3.4rem); line-height: 1.12; letter-spacing: -0.04em; }
.source-note { margin-block: 2.5rem; padding: 1rem 1.2rem; border: 1px solid var(--line); background: var(--paper-bright); color: var(--ink-soft); font-size: 0.8rem; line-height: 1.55; }
.source-note strong { font-family: var(--mono); font-size: 0.68rem; letter-spacing: .06em; text-transform: uppercase; }

.editorial-asset { position: relative; overflow: hidden; margin: 3rem 0 0; border: 1px solid var(--line); background: #10171b; }
.editorial-asset img { width: 100%; height: 100%; object-fit: cover; transform: translate3d(0, var(--asset-y, 0), 0) scale(var(--asset-scale, 1.045)); transition: transform 120ms linear; will-change: transform; }
.editorial-asset figcaption { position: absolute; right: 0; bottom: 0; left: 0; padding: 1.2rem; color: rgba(255,255,255,.82); background: linear-gradient(transparent, rgba(6,10,12,.88)); font: 650 .62rem/1.45 var(--mono); text-transform: uppercase; }
.editorial-asset::after { position: absolute; right: 0; bottom: 0; left: 0; height: 2px; content: ""; background: var(--blue); transform: scaleX(0); transform-origin: left; transition: transform 900ms cubic-bezier(.22,1,.36,1) 180ms; }
.editorial-asset.is-visible::after { transform: scaleX(1); }
.editorial-asset--full { width: 100%; aspect-ratio: 2 / 1; margin: 0; border-inline: 0; }
.editorial-asset--full img { object-position: center; }
.editorial-asset--dark { min-height: 520px; }
.logic-poster { aspect-ratio: 16 / 9; margin-top: 3.5rem; border-color: rgba(255,255,255,.28); box-shadow: 0 26px 70px rgba(1,13,48,.42); }
.history-asset { aspect-ratio: 3 / 2; margin: 2.5rem 0 3.5rem; }

.material-band { color: white; background: #172027; }
.material-grid { display: grid; grid-template-columns: .82fr 1.18fr; gap: clamp(2.5rem, 7vw, 8rem); align-items: center; }
.material-band .section-number { color: #83a8ff; }
.material-band h2 { color: white; }
.material-band p { color: #c7ced0; }

.scrolly-section { padding-block: clamp(4rem, 8vw, 7rem); background: var(--paper-bright); }
.scrolly-layout { display: grid; grid-template-columns: minmax(0, .78fr) minmax(420px, 1.22fr); gap: clamp(2rem, 7vw, 7rem); align-items: start; }
.scrolly-steps { padding-bottom: 20vh; }
.scrolly-step { min-height: 74vh; display: flex; flex-direction: column; justify-content: center; opacity: .44; transition: opacity 240ms ease; }
.scrolly-step.is-active { opacity: 1; }
.scrolly-step h3 { margin: 0 0 1rem; font-family: var(--serif); font-size: clamp(2rem, 4vw, 3.5rem); font-weight: 500; line-height: 1; letter-spacing: -.045em; }
.scrolly-step p { color: var(--ink-soft); font-family: var(--serif); font-size: 1.12rem; line-height: 1.65; }
.chip-scene { position: sticky; top: 7vh; display: grid; min-width: 0; min-height: 86vh; margin: 0; place-items: center; overflow: hidden; border: 1px solid var(--line); background: #e9edf4; }
.chip-scene > img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; opacity: 0; transform: scale(1.11) translate3d(0,12px,0); filter: saturate(.78) contrast(1.02); transition: opacity 650ms ease, transform 1.1s cubic-bezier(.22,1,.36,1), filter 650ms ease; }
.chip-scene [data-stage-image="gate"], .chip-scene [data-stage-image="flow"] { object-fit: contain; background: #f7f1e7; }
.chip-scene[data-active-stage="sand"] [data-stage-image="sand"],
.chip-scene[data-active-stage="crystal"] [data-stage-image="crystal"],
.chip-scene[data-active-stage="gate"] [data-stage-image="gate"],
.chip-scene[data-active-stage="flow"] [data-stage-image="flow"],
.chip-scene > img.is-active { opacity: 1; transform: scale(1.02) translate3d(0,0,0); filter: saturate(1) contrast(1); }
.chip-scene[data-active-stage="flow"] [data-stage-image="flow"] { transform: scale(1.08) translate3d(-1%,0,0); }
.chip-scene::after { position: absolute; inset: 0; content: ""; pointer-events: none; background: linear-gradient(180deg, rgba(255,255,255,.12), transparent 18%, transparent 76%, rgba(10,15,18,.5)); }
.scene-caption { position: absolute; z-index: 2; right: 1.2rem; bottom: 1rem; left: 1.2rem; display: flex; justify-content: space-between; gap: 1rem; padding-top: .8rem; border-top: 1px solid rgba(255,255,255,.55); color: white; text-shadow: 0 1px 8px rgba(0,0,0,.85); font: 650 .61rem/1.45 var(--mono); text-transform: uppercase; }

.logic-band { color: white; background: var(--blue-dark); }
.logic-band .article-copy h2, .logic-band .article-copy p { color: white; }
.logic-band .section-number { color: #b9ccff; }
.logic-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; margin-top: 4rem; }
.logic-card { min-height: 280px; padding: 1.5rem; border: 1px solid rgba(255,255,255,.22); background: rgba(0,0,0,.12); }
.logic-card__number { color: #b9ccff; font: 700 .62rem var(--mono); }
.logic-card h3 { margin: 3rem 0 .8rem; font-family: var(--serif); font-size: 2rem; font-weight: 500; }
.logic-card p { color: #dce5ff !important; font: 1rem/1.6 var(--sans) !important; }
.logic-symbol { display: flex; align-items: center; justify-content: center; height: 86px; margin-top: 1.5rem; font: 700 1.5rem var(--mono); }
.logic-symbol span { display: grid; width: 48px; height: 48px; place-items: center; border: 1px solid rgba(255,255,255,.45); }
.logic-symbol i { width: 30px; height: 1px; background: rgba(255,255,255,.5); }

.quiz { margin-block: 4rem; padding: clamp(1.4rem, 4vw, 2.5rem); border: 1px solid var(--line); background: var(--paper-bright); }
.quiz legend { padding: 0 .6rem; font-family: var(--serif); font-size: 1.35rem; }
.quiz__answers { display: grid; gap: .65rem; margin-top: 1.2rem; }
.quiz button { min-height: 50px; padding: .8rem 1rem; text-align: left; border: 1px solid var(--line); color: var(--ink); background: white; cursor: pointer; }
.quiz button:hover:not(:disabled), .quiz button:focus-visible { border-color: var(--blue); }
.quiz button.is-correct { color: #15492d; border-color: #39805a; background: #e0f3e7; }
.quiz button.is-wrong { color: #812f2f; border-color: #ba5555; background: #f8e2e0; }
.quiz__result { min-height: 1.5em; margin: 1rem 0 0 !important; color: var(--ink-soft) !important; font: .88rem/1.5 var(--sans) !important; }

.takeaway-section { background: #e4e9f2; }
.takeaway-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; margin-top: 3rem; counter-reset: takeaway; }
.takeaway { padding: clamp(1.4rem, 3vw, 2rem); border-top: 2px solid var(--ink); background: rgba(255,255,255,.48); counter-increment: takeaway; }
.takeaway::before { content: "0" counter(takeaway); color: var(--blue); font: 700 .65rem var(--mono); }
.takeaway h3 { margin: 2.5rem 0 .7rem; font-size: 1.2rem; }
.takeaway p { margin: 0; font: .94rem/1.6 var(--sans); }

.connections { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.connection-card { min-height: 230px; padding: 1.6rem; border: 1px solid var(--line); background: var(--paper-bright); }
.connection-card[aria-disabled="true"] { opacity: .62; }
.connection-card p { font: .92rem/1.6 var(--sans); }
.connection-card__meta { color: var(--blue-dark) !important; font: 700 .62rem var(--mono) !important; letter-spacing: .08em; text-transform: uppercase; }
.connection-card h3 { margin: 2.5rem 0 .8rem; }

.sources-list { display: grid; margin: 3rem 0 0; padding: 0; border-top: 1px solid var(--line); list-style: none; }
.sources-list li { display: grid; grid-template-columns: 3rem minmax(0, 1fr); gap: 1rem; padding: 1.4rem 0; border-bottom: 1px solid var(--line); font: .88rem/1.55 var(--sans); }
.sources-list span { color: var(--blue); font: 700 .64rem var(--mono); }
.sources-list strong { display: block; margin-bottom: .25rem; }
.sources-list small { color: var(--ink-soft); font-size: .77rem; }

.archive-footer { color: #aeb8ba; background: var(--graphite); }
.archive-footer__inner { display: grid; grid-template-columns: 1fr auto; gap: 2rem; align-items: end; padding-block: 4rem; }
.archive-footer h2 { max-width: 12ch; margin: 0; color: white; font-family: var(--serif); font-size: clamp(2.2rem, 5vw, 4.6rem); font-weight: 500; line-height: .95; letter-spacing: -.05em; }
.archive-footer a { color: white; }

.archive-index-hero { padding-block: clamp(5rem, 12vw, 10rem); border-bottom: 1px solid var(--line); }
.archive-index-hero__grid { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 2rem; align-items: end; }
.archive-index-hero h1 { max-width: 14ch; margin: 0; font-family: var(--serif); font-size: clamp(3.5rem, 8vw, 7.8rem); font-weight: 500; line-height: .9; letter-spacing: -.065em; }
.archive-index-hero p { max-width: 55ch; color: var(--ink-soft); font-family: var(--serif); font-size: 1.22rem; line-height: 1.65; }
.archive-count { color: var(--blue); font: 500 clamp(4rem, 10vw, 8rem)/.8 var(--serif); }
.archive-list { display: grid; gap: 1rem; padding-block: 4rem 8rem; }
.archive-card { display: grid; grid-template-columns: 160px minmax(0, 1.3fr) minmax(260px, .7fr) auto; gap: 2rem; align-items: start; padding: 2rem 0; border-top: 1px solid var(--line); }
.archive-card__meta { margin: .3rem 0 0; color: var(--blue-dark); font: 700 .65rem var(--mono); }
.archive-card h2 { margin: 0; font-family: var(--serif); font-size: clamp(1.8rem, 3vw, 2.7rem); font-weight: 500; line-height: 1.05; }
.archive-card h2 a { text-decoration: none; }
.archive-card > p:not(.archive-card__meta) { margin: 0; color: var(--ink-soft); line-height: 1.6; }
.text-action { white-space: nowrap; color: var(--blue-dark); font-size: .78rem; font-weight: 700; }

[data-reveal] { opacity: 1; transform: none; }
.js [data-reveal] { opacity: 0; transform: translateY(22px); transition: opacity 620ms ease, transform 620ms ease; }
.js [data-reveal].is-visible { opacity: 1; transform: none; }

@keyframes asset-sheen { 0%, 58% { transform: translateX(-110%); } 82%, 100% { transform: translateX(110%); } }

@media (max-width: 900px) {
  .archive-nav a:not(:last-child) { display: none; }
  .article-hero__inner, .material-grid, .scrolly-layout { grid-template-columns: 1fr; }
  .article-hero__inner { align-content: center; }
  .hero-asset { width: min(90vw, 620px); aspect-ratio: 16 / 10; margin-inline: auto; }
  .scrolly-steps { padding-bottom: 0; }
  .scrolly-step { min-height: auto; padding-block: 3.5rem; opacity: 1; }
  .chip-scene { position: sticky; z-index: 3; top: 70px; min-height: 48vh; order: -1; }
  .logic-grid, .takeaway-grid { grid-template-columns: 1fr; }
  .logic-card { min-height: auto; }
  .archive-card { grid-template-columns: 110px 1fr; }
  .archive-card > p:not(.archive-card__meta), .archive-card .text-action { grid-column: 2; }
}

@media (max-width: 600px) {
  .archive-shell, .article-copy, .article-copy--wide { width: min(calc(100% - 1.25rem), var(--wide)); }
  .archive-header__inner { min-height: 62px; }
  .archive-brand { font-size: .68rem; }
  .archive-nav { gap: .75rem; }
  .article-hero { min-height: auto; }
  .article-hero__inner { padding-block: 4rem 3rem; }
  .article-hero h1 { font-size: clamp(3.2rem, 15vw, 5.1rem); }
  .hero-asset { width: 100%; }
  .article-section { padding-block: 4.5rem; }
  .editorial-asset--full { aspect-ratio: 4 / 3; }
  .editorial-asset--full img { object-position: 48% center; }
  .editorial-asset--dark { min-height: 0; aspect-ratio: 3 / 2; }
  .chip-scene { min-height: 390px; }
  .connections { grid-template-columns: 1fr; }
  .archive-footer__inner, .archive-index-hero__grid { grid-template-columns: 1fr; }
  .archive-card { grid-template-columns: 1fr; gap: .8rem; }
  .archive-card > p:not(.archive-card__meta), .archive-card .text-action { grid-column: auto; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .001ms !important; animation-iteration-count: 1 !important; transition-duration: .001ms !important; }
  [data-reveal] { opacity: 1 !important; transform: none !important; }
  .scrolly-step { opacity: 1; }
  .chip-scene { position: relative; top: auto; }
  .chip-scene > img { opacity: 0; transform: none; }
  .chip-scene > img:last-of-type { opacity: 1; }
  [data-scroll-fx] img { transform: none !important; }
}

/* Day 002 · Binary editorial direction */
.binary-article {
  --blue: #087c72;
  --blue-dark: #075f59;
  --paper: #f2eee4;
  --paper-bright: #faf7ef;
  --graphite: #10201f;
}
.binary-hero { background: #10201f; }
.binary-hero .hero-asset { border-color: rgba(8, 124, 114, .45); }
.binary-ink-band { color: #e8efeb; background: #10201f; }
.binary-ink-band h2, .binary-ink-band .lead { color: #fff; }
.binary-ink-band p { color: #c4d0ca; }
.binary-ink-band .source-note { color: #dfe8e3; border-color: rgba(255,255,255,.24); background: rgba(255,255,255,.05); }
.binary-history-band { background: #dce7df; }
.binary-poster { background: #10201f; }
.binary-poster--paper { background: #eee6d5; }
.binary-poster img { object-fit: contain; }
.binary-scrolly { background: #091513; }
.binary-scrolly .scrolly-step h3 { color: #f7faf8; }
.binary-scrolly .scrolly-step p { color: #c3d0ca; }
.binary-scrolly .scrolly-step .section-number { color: #62b9ae; }
.binary-scene { border-color: rgba(87, 186, 175, .28); background: #07100f; }
.reflection-list { display: grid; gap: 1rem; margin: 2.5rem 0 0; padding: 0; list-style: none; counter-reset: reflection; }
.reflection-list li { position: relative; padding: 1.25rem 1.25rem 1.25rem 4rem; border-top: 1px solid var(--line); font: 1rem/1.65 var(--sans); counter-increment: reflection; }
.reflection-list li::before { position: absolute; left: 0; top: 1.3rem; color: var(--blue-dark); font: 700 .68rem var(--mono); content: "0" counter(reflection); }
.connection-card { display: block; color: inherit; text-decoration: none; transition: transform 180ms ease, border-color 180ms ease, background 180ms ease; }
.connection-card:hover, .connection-card:focus-visible { transform: translateY(-4px); border-color: var(--blue); background: #fff; }

@media (min-width: 901px) {
  .binary-hero h1 { max-width: 14ch; font-size: clamp(3.6rem, 5.1vw, 5rem); }
  .binary-hero .article-hero__inner { padding-block: clamp(4rem, 6vw, 6rem); }
}

@media (max-width: 600px) {
  .binary-poster { aspect-ratio: 4 / 3; }
  .binary-poster img { object-position: center; }
}

@media (prefers-reduced-motion: reduce) {
  .connection-card:hover, .connection-card:focus-visible { transform: none; }
}

/* Day 003 · Perceptron editorial direction */
.perceptron-article {
  --blue: #7547d8;
  --blue-dark: #5630a8;
  --paper: #f1ecdf;
  --paper-bright: #faf6ec;
  --graphite: #161126;
}
.perceptron-hero { background: #161126; }
.perceptron-hero h1 { max-width: 14ch; }
.perceptron-hero .hero-asset { aspect-ratio: 3 / 2; border-color: rgba(148, 102, 235, .42); }
.perceptron-hero .hero-asset img { object-position: center; }
.perceptron-poster { background: #efe5d0; }
.perceptron-poster img { object-fit: cover; }
.perceptron-equation-band { background: #e8e0f1; }
.equation-card { margin: 3rem 0; padding: clamp(1.4rem, 4vw, 2.6rem); border: 1px solid rgba(86, 48, 168, .24); background: rgba(255,255,255,.58); box-shadow: 0 22px 60px rgba(48,31,82,.08); }
.equation-card p { margin: 0; color: #24183c; font: 600 clamp(1.6rem, 4.2vw, 3rem)/1.45 var(--mono); letter-spacing: -.045em; }
.equation-card p + p { margin-top: .7rem; padding-top: .7rem; border-top: 1px solid rgba(86,48,168,.18); }
.equation-card span { display: inline-block; width: 6.5rem; color: #7547d8; font-size: .62em; letter-spacing: .04em; text-transform: uppercase; }
.perceptron-scrolly { color: #f4f0ff; background: #0e0b18; }
.perceptron-scrolly .scrolly-step h3 { color: white; }
.perceptron-scrolly .scrolly-step p { color: #c9c1d8; }
.perceptron-scrolly .section-number { color: #a987ef; }
.perceptron-scene { border-color: rgba(169,135,239,.32); background: #101017; }
.perceptron-scene > img { object-fit: cover; }
.perceptron-history-band { background: #d9d1bd; }
.perceptron-article .history-layout { display: grid; grid-template-columns: .8fr 1.2fr; gap: clamp(2rem, 6vw, 6rem); align-items: center; }
.perceptron-article .history-layout .history-asset { margin: 0; aspect-ratio: 3 / 2; }
.xor-asset { width: min(100%, 720px); aspect-ratio: 1; margin: 3rem auto; background: #efe0bd; }
.xor-asset img { object-fit: cover; }
.perceptron-ink-band { color: white; background: #161126; }
.perceptron-ink-band h2 { color: white; }
.perceptron-ink-band p { color: #d0c9da; }
.perceptron-ink-band .section-number { color: #a987ef; }

@media (min-width: 901px) {
  .perceptron-hero .article-hero__inner { grid-template-columns: 1.05fr .95fr; padding-block: clamp(4rem, 6vw, 6rem); }
  .perceptron-hero h1 { font-size: clamp(3.45rem, 5vw, 5.25rem); }
}

@media (max-width: 900px) {
  .perceptron-article .history-layout { grid-template-columns: 1fr; }
}

@media (max-width: 600px) {
  .perceptron-hero h1 { font-size: clamp(2.85rem, 13vw, 4.6rem); }
  .perceptron-poster { aspect-ratio: 4 / 3; }
  .perceptron-poster img { object-position: center; }
  .equation-card span { width: 5rem; }
  .perceptron-scene { min-height: min(390px, calc(100vw - 1.25rem)); aspect-ratio: 1; }
}