/* Hallmark · macrostructure: Workbench · H8 product capture, custom art direction
 * theme: custom (redesign) · vibe: "iridescent, luminous, warm-to-cool gradient, no blue" · paper: oklch(97.5% 0.010 40) · accent: oklch(66% 0.16 35) → oklch(64% 0.15 300)
 * display: -apple-system/SF Pro · body: -apple-system/SF Pro · axes: light / grotesque-sans-system / chromatic-coral-to-violet
 * studied: no · context: user feedback (no blue, iridescent palette from real product captures, real Φ logo asset, centred hero + iPad frame, de-carded method, Ft3 wordmark footer) · nav: N10 · footer: Ft3 · contrast: pass (40–41) · slop: pass (42–45)
 * honest: pass (46) · chrome: pass (47) · tokens: pass (48) · responsive: pass (34, 49, 50–57) · pre-emit critique: P5 H4 E5 S4 R4 V5
 */
@import url("tokens.css");

* { box-sizing: border-box; }
html, body { margin: 0; overflow-x: clip; }
html { scroll-behavior: smooth; background: var(--color-paper); }
body { background: var(--color-paper); color: var(--color-ink); font-family: var(--font-body); font-size: var(--text-base); line-height: 1.5; }
button, input { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
button { cursor: pointer; }
button:disabled { opacity: 0.55; cursor: not-allowed; }
a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
h1, h2, h3, p { margin: 0; }
h1, h2, h3 { font-family: var(--font-display); font-style: normal; font-weight: 600; letter-spacing: -0.02em; line-height: 1.04; overflow-wrap: anywhere; min-width: 0; }
:focus-visible { outline: 2px solid var(--color-focus); outline-offset: 3px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; }
.page-shell { overflow: clip; }

.site-nav { position: sticky; top: 0; z-index: 10; padding: var(--space-md) var(--page-gutter); pointer-events: none; transition: padding var(--dur-medium) var(--ease-out); }
.site-nav__inner { width: min(100%, var(--content-max)); min-height: 3.6rem; margin: auto; padding: var(--space-xs) var(--space-sm) var(--space-xs) var(--space-lg); display: flex; align-items: center; gap: var(--space-lg); pointer-events: auto; background: var(--color-paper-raised); border: var(--rule-hair) solid var(--color-rule); border-radius: var(--radius-lg); box-shadow: var(--shadow-float); backdrop-filter: blur(1.25rem) saturate(1.3); -webkit-backdrop-filter: blur(1.25rem) saturate(1.3); transition: background-color var(--dur-medium) var(--ease-out), border-color var(--dur-medium) var(--ease-out), box-shadow var(--dur-medium) var(--ease-out), padding var(--dur-medium) var(--ease-out); }
.site-nav.is-floating { padding-top: var(--space-sm); }
.site-nav.is-floating .site-nav__inner { background: color-mix(in oklch, var(--color-paper-raised) 92%, var(--color-paper) 8%); box-shadow: var(--shadow-float), 0 0.15rem 0.4rem oklch(35% 0.045 320 / 0.08); }
.brand { display: inline-flex; flex: 0 0 auto; align-items: center; gap: var(--space-xs); font-family: var(--font-display); font-weight: 700; font-size: 1.15rem; letter-spacing: -0.015em; white-space: nowrap; }
.brand-mark { display: block; width: auto; height: 1.65rem; }
.site-nav__links { display: none; gap: var(--space-lg); margin-inline: auto; font-size: var(--text-sm); font-weight: 600; }
.site-nav__links a, .footer__meta a { position: relative; white-space: nowrap; }
.site-nav__links a::after, .text-link::after { content: ""; position: absolute; inset-inline: 0; bottom: -0.3rem; height: 1px; background: var(--color-accent); transform: scaleX(0); transform-origin: left; transition: transform var(--dur-short) var(--ease-out); }
.nav-menu { width: 2.75rem; height: 2.75rem; margin-left: auto; display: grid; place-content: center; gap: 0.3rem; border: 0; background: transparent; color: var(--color-ink); border-radius: 50%; }
.nav-menu span:not(.sr-only) { display: block; width: 1.1rem; height: 1.5px; background: currentColor; transition: transform var(--dur-short) var(--ease-out); }
.nav-menu[aria-expanded="true"] span:first-child { transform: translateY(0.22rem) rotate(45deg); }
.nav-menu[aria-expanded="true"] span:nth-child(2) { transform: translateY(-0.22rem) rotate(-45deg); }
.button { min-height: 3rem; display: inline-flex; align-items: center; justify-content: center; padding: 0.75rem 1.2rem; border: var(--rule-hair) solid var(--color-ink); border-radius: 999px; background: var(--color-ink); color: var(--color-paper); font-weight: 600; font-size: var(--text-sm); white-space: nowrap; transition: background-color var(--dur-short) var(--ease-out), color var(--dur-short) var(--ease-out), border-color var(--dur-short) var(--ease-out), transform var(--dur-instant) var(--ease-out); }
.button--nav { display: none; margin-left: auto; }
.button--large { min-height: 3.6rem; padding-inline: var(--space-lg); }
.button:active { transform: translateY(1px) scale(0.985); }
.button[disabled] { opacity: 0.55; cursor: not-allowed; }
.text-link { position: relative; display: inline-flex; align-items: center; font-weight: 600; font-size: var(--text-sm); white-space: nowrap; }
.mobile-menu { width: min(100%, var(--content-max)); margin: var(--space-xs) auto 0; padding: var(--space-md); display: grid; gap: var(--space-xs); pointer-events: auto; border: var(--rule-hair) solid var(--color-rule); border-radius: var(--radius-md); background: var(--color-paper-raised); box-shadow: var(--shadow-float); backdrop-filter: blur(1.25rem); }
.mobile-menu[hidden] { display: none; }
.mobile-menu a { padding: var(--space-sm); font-weight: 700; }

.hero { width: min(100%, var(--content-max)); margin: 0 auto; padding: clamp(3.5rem, 6vw, 6rem) var(--page-gutter) var(--space-2xl); display: grid; justify-items: center; gap: var(--space-2xl); text-align: center; }
.hero__copy { max-width: 54rem; display: grid; justify-items: center; }
.eyebrow { color: var(--color-ink-soft); font-family: var(--font-body); font-size: var(--text-xs); font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase; }
.hero h1 { max-width: 16ch; margin-top: var(--space-lg); font-size: clamp(2.9rem, 5.4vw, 6rem); font-weight: 700; text-wrap: balance; }
.hero h1 strong { color: var(--color-accent); font-weight: 700; }
.hero__lede { max-width: 44rem; margin-top: var(--space-lg); color: var(--color-ink-soft); font-size: clamp(1.04rem, 1.5vw, 1.25rem); line-height: 1.65; text-wrap: pretty; }
.hero__actions { display: flex; flex-wrap: wrap; justify-content: center; align-items: center; gap: var(--space-lg); margin-top: var(--space-xl); }
.hero__product { position: relative; width: min(100%, 62rem); min-width: 0; margin: 0; }
.hero__product::before { content: ""; position: absolute; inset: -12% -10%; background: var(--gradient-wash); filter: blur(3.5rem); z-index: -1; pointer-events: none; }
.hero__product figcaption { margin-inline: auto; }
.device { position: relative; padding: clamp(0.5rem, 1.1vw, 0.85rem); border-radius: clamp(1.2rem, 2.4vw, 2.1rem); background: linear-gradient(160deg, oklch(46% 0.012 300) 0%, oklch(28% 0.010 300) 42%, oklch(38% 0.012 300) 100%); box-shadow: var(--shadow-glass), 0 0 0 1px oklch(22% 0.01 300 / 0.5); }
.device__screen { position: relative; overflow: hidden; aspect-ratio: 1.333; border-radius: clamp(0.8rem, 1.6vw, 1.4rem); background: var(--color-paper); box-shadow: inset 0 0 0 1px oklch(20% 0.01 300 / 0.35); }
.device__screen img { width: 100%; height: 100%; object-fit: cover; object-position: top center; }
.hero__product figcaption { position: relative; z-index: 1; max-width: 22rem; margin-top: var(--space-lg); color: var(--color-muted); font-size: var(--text-sm); }

.tour, .method, .roles { width: min(100%, var(--content-max)); margin: 0 auto; padding: var(--space-3xl) var(--page-gutter); }
.tour, .roles { padding-top: var(--space-xl); }
.tour__intro { display: grid; gap: var(--space-lg); max-width: 50rem; }
.tour h2, .method h2, .roles h2, .closing h2, .chat-detail h2, .teachers h2 { font-size: var(--text-2xl); font-weight: 600; }
.tour__intro > p:last-child { max-width: 39rem; color: var(--color-ink-soft); font-size: var(--text-lg); line-height: 1.6; }
/* The track bleeds past the container to the right viewport edge, so the next card runs
 * off-screen instead of being sliced at the container's padding edge. --bleed is that
 * distance: the section gutter plus whatever margin sits outside a maxed-out container. */
.exp-carousel { --bleed: calc((100vw - min(100vw, var(--content-max))) / 2 + var(--page-gutter)); --visible-w: calc(min(100vw, var(--content-max)) - 2 * var(--page-gutter) + var(--bleed)); margin-top: var(--space-md); margin-right: calc(-1 * var(--bleed)); }
.exp-track { display: flex; gap: var(--space-lg); margin: 0; padding: 0.25rem calc(var(--bleed) + 0.25rem) var(--space-sm) 0.25rem; list-style: none; overflow-x: auto; scroll-snap-type: x mandatory; scroll-padding-right: var(--bleed); scrollbar-width: none; }
.exp-track::-webkit-scrollbar { display: none; }
.exp-card { flex: 0 0 auto; width: min(82vw, 24rem); scroll-snap-align: start; display: grid; gap: var(--space-md); }
.exp-card__shot { position: relative; margin: 0; min-width: 0; }
.exp-card__shot .device { width: 100%; }
.exp-card__caption { max-width: 30rem; color: var(--color-ink-soft); font-size: var(--text-base); line-height: 1.6; }
.exp-card__caption b { color: var(--color-ink); font-weight: 600; }
.exp-nav { display: flex; gap: var(--space-sm); margin-top: var(--space-lg); padding-right: var(--bleed); justify-content: flex-end; }
.exp-nav__btn { width: 2.75rem; height: 2.75rem; padding: 0; border: var(--rule-hair) solid var(--color-rule-strong); border-radius: 50%; background: var(--color-paper-raised); color: var(--color-ink); display: grid; place-items: center; transition: background-color var(--dur-short) var(--ease-out), color var(--dur-short) var(--ease-out), opacity var(--dur-short) var(--ease-out); }
.exp-nav__btn svg { width: 1.1rem; height: 1.1rem; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.exp-nav__btn:disabled { opacity: 0.35; cursor: not-allowed; }

.method { display: grid; gap: var(--space-xl); padding-top: var(--space-xl); border-top: var(--rule-hair) solid var(--color-rule); }
.method__head { max-width: 48rem; display: grid; gap: var(--space-md); }
.method__body { display: grid; gap: var(--space-xl); }
.method__lead { max-width: 40rem; color: var(--color-ink-soft); font-size: var(--text-lg); line-height: 1.62; }
.method__steps { display: grid; gap: var(--space-xl) var(--space-2xl); margin: 0; padding: 0; list-style: none; }
.method__steps li { display: grid; grid-template-rows: auto auto auto; align-content: start; gap: var(--space-sm); padding-top: var(--space-md); border-top: 2px solid var(--color-ink); }
.chat-steps li > span, .method__steps li > span { color: var(--color-muted); font-family: var(--font-body); font-size: var(--text-xs); font-weight: 700; letter-spacing: 0.04em; text-transform: uppercase; }
.chat-steps strong, .method__steps strong { font-family: var(--font-display); font-weight: 600; font-size: clamp(1.3rem, 1.8vw, 1.7rem); letter-spacing: -0.02em; line-height: 1.15; text-wrap: balance; }
.chat-steps p, .method__steps p { max-width: 38rem; color: var(--color-ink-soft); font-size: var(--text-sm); line-height: 1.6; }
.chat-steps { display: grid; gap: var(--space-xl) var(--space-2xl); margin: var(--space-xl) 0 0; padding: 0; list-style: none; }
.chat-steps li { display: grid; grid-template-rows: auto auto auto auto; align-content: start; gap: var(--space-sm); padding-top: var(--space-md); border-top: 2px solid var(--color-ink); }

/* Each step carries a small chat-surface demo — one shared frame so the four read as a set.
 * Solid accent only, no gradients: the orange marks whatever the demo is highlighting. */
.step-demo { height: 10.5rem; margin-top: var(--space-xs); padding: var(--space-md); display: flex; flex-direction: column; justify-content: center; gap: 0.4rem; overflow: hidden; border: var(--rule-hair) solid var(--color-rule); border-radius: var(--radius-md); background: var(--color-paper-raised); }
.step-demo--center { align-items: center; justify-content: center; gap: var(--space-md); perspective: 60rem; }

.mini-bubble { width: fit-content; max-width: 92%; padding: 0.45rem 0.6rem; border-radius: 0.7rem 0.7rem 0.7rem 0.2rem; background: var(--color-paper); border: var(--rule-hair) solid var(--color-rule); font-size: 0.72rem; line-height: 1.35; color: var(--color-ink); }
.mini-bubble--marked { border-color: var(--color-accent); }
.mini-bubble--me { align-self: flex-end; border-radius: 0.7rem 0.7rem 0.2rem 0.7rem; background: var(--color-accent); border-color: transparent; color: white; font-weight: 700; }
.mini-bubble--ok { color: var(--color-success); border-color: color-mix(in oklch, var(--color-success) 45%, transparent); font-weight: 600; }
.mini-tag { display: block; margin-bottom: 0.15rem; font-size: 0.58rem; font-weight: 700; letter-spacing: 0.05em; text-transform: uppercase; color: var(--color-muted); }
.mini-tag--accent { color: var(--color-accent); }
.mini-ask { font-size: 0.68rem; font-style: italic; color: var(--color-muted); }

/* Staggered entrance for the bubble demos. The stagger lives in the keyframe offsets rather
 * than animation-delay so every element exits on the same beat and the panel resets as one. */
.mini-pop { opacity: 0; animation-duration: 5.2s; animation-timing-function: var(--ease-out); animation-iteration-count: infinite; }
.step-demo .mini-pop:nth-child(1) { animation-name: mini-pop-1; }
.step-demo .mini-pop:nth-child(2) { animation-name: mini-pop-2; }
.step-demo .mini-pop:nth-child(3) { animation-name: mini-pop-3; }
@keyframes mini-pop-1 { 0% { opacity: 0; transform: translateY(0.35rem); } 7%, 84% { opacity: 1; transform: none; } 94%, 100% { opacity: 0; transform: none; } }
@keyframes mini-pop-2 { 0%, 20% { opacity: 0; transform: translateY(0.35rem); } 27%, 84% { opacity: 1; transform: none; } 94%, 100% { opacity: 0; transform: none; } }
@keyframes mini-pop-3 { 0%, 42% { opacity: 0; transform: translateY(0.35rem); } 49%, 84% { opacity: 1; transform: none; } 94%, 100% { opacity: 0; transform: none; } }

.mini-toggle { position: relative; display: flex; gap: 0.25rem; padding: 0.22rem; border-radius: 999px; background: color-mix(in oklch, var(--color-ink) 7%, transparent); }
.mini-toggle__thumb { position: absolute; top: 0.22rem; bottom: 0.22rem; left: 0.22rem; width: calc(50% - 0.345rem); border-radius: 999px; background: var(--color-accent); animation: mini-toggle 5.2s var(--ease-in-out) infinite; }
.mini-toggle__opt { position: relative; z-index: 1; flex: 1; padding: 0.28rem 0.25rem; text-align: center; font-size: 0.64rem; font-weight: 700; }
.mini-toggle__opt:nth-of-type(1) { animation: mini-opt-a 5.2s var(--ease-in-out) infinite; }
.mini-toggle__opt:nth-of-type(2) { animation: mini-opt-b 5.2s var(--ease-in-out) infinite; }
@keyframes mini-toggle { 0%, 42% { transform: translateX(0); } 54%, 94% { transform: translateX(calc(100% + 0.25rem)); } 100% { transform: translateX(0); } }
@keyframes mini-opt-a { 0%, 42% { color: white; } 54%, 94% { color: var(--color-ink-soft); } 100% { color: white; } }
@keyframes mini-opt-b { 0%, 42% { color: var(--color-ink-soft); } 54%, 94% { color: white; } 100% { color: var(--color-ink-soft); } }
/* Same question, two answers — the reply cross-fades in step with the toggle. */
.mode-reply { display: grid; }
.mode-reply > * { grid-area: 1 / 1; }
.mode-reply__a { animation: mode-a 5.2s var(--ease-out) infinite; }
.mode-reply__b { animation: mode-b 5.2s var(--ease-out) infinite; }
@keyframes mode-a { 0%, 42% { opacity: 1; } 48%, 94% { opacity: 0; } 100% { opacity: 1; } }
@keyframes mode-b { 0%, 42% { opacity: 0; } 48%, 94% { opacity: 1; } 100% { opacity: 0; } }

.flip-card { position: relative; width: min(100%, 13rem); height: 3.9rem; transform-style: preserve-3d; animation: flip-card 5.2s var(--ease-in-out) infinite; }
.flip-card__face { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; padding: 0 0.7rem; text-align: center; font-size: 0.72rem; font-weight: 600; line-height: 1.25; border-radius: var(--radius-sm); backface-visibility: hidden; background: var(--color-paper); border: var(--rule-hair) solid var(--color-rule-strong); color: var(--color-ink); }
.flip-card__face--back { transform: rotateY(180deg); color: white; background: var(--color-accent); border-color: transparent; }
@keyframes flip-card { 0%, 40% { transform: rotateY(0deg); } 52%, 92% { transform: rotateY(180deg); } 100% { transform: rotateY(360deg); } }
.flip-dots { display: flex; gap: 0.3rem; }
.flip-dots i { width: 0.3rem; height: 0.3rem; border-radius: 50%; background: var(--color-rule-strong); }
.flip-dots i:first-child { background: var(--color-accent); }

.chat-detail { width: min(100%, var(--content-max)); margin: 0 auto; padding: var(--space-xl) var(--page-gutter) var(--space-3xl); border-top: var(--rule-hair) solid var(--color-rule); }
.chat-detail__intro { max-width: 40rem; display: grid; gap: var(--space-md); }
.chat-detail__lead { color: var(--color-ink-soft); font-size: var(--text-lg); line-height: 1.62; }


.teachers { width: min(100%, var(--content-max)); margin: 0 auto; padding: var(--space-xl) var(--page-gutter) var(--space-3xl); border-top: var(--rule-hair) solid var(--color-rule); }
.teachers__head { max-width: 48rem; display: grid; gap: var(--space-md); }
.teachers__lead { color: var(--color-ink-soft); font-size: var(--text-lg); line-height: 1.62; }
.teachers__body { display: grid; gap: var(--space-2xl); margin-top: var(--space-2xl); align-items: start; }
.teachers__shot { margin: 0; min-width: 0; }
.teachers__shot figcaption { margin-top: var(--space-md); color: var(--color-muted); font-size: var(--text-sm); }
.teachers__shot .device__screen img { transition: opacity var(--dur-short) var(--ease-out); }
.teachers__shot .device__screen img.is-swapping { opacity: 0; }
.teachers__panel { min-width: 0; display: grid; gap: var(--space-xl); align-content: start; }
/* Two labelled groups — capabilities, then the real-class figures — so the panel reads
 * as a hierarchy instead of one flat run of cards followed by a paragraph. */
.teachers__group { display: grid; gap: var(--space-md); }
.teachers__subhead { color: var(--color-muted); font-family: var(--font-body); font-size: var(--text-xs); font-weight: 700; letter-spacing: 0.05em; text-transform: uppercase; }
.teacher-tools { display: grid; gap: var(--space-sm); margin: 0; padding: 0; list-style: none; }
.teacher-tools li { border: var(--rule-hair) solid var(--color-rule); border-radius: var(--radius-md); background: var(--color-paper-raised); transition: border-color var(--dur-short) var(--ease-out), background-color var(--dur-short) var(--ease-out); }
.teacher-tools li.is-active { border-color: var(--color-accent); background: color-mix(in oklch, var(--color-accent) 8%, var(--color-paper-raised)); }
.teacher-tools button { display: grid; gap: var(--space-2xs); width: 100%; padding: var(--space-md); border: 0; background: none; font: inherit; text-align: left; color: inherit; cursor: pointer; }
.teacher-tools b { font-family: var(--font-display); font-weight: 600; font-size: 0.98rem; letter-spacing: -0.01em; }
.teacher-tools span { color: var(--color-muted); font-size: var(--text-sm); line-height: 1.4; }
.stat-row { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-md); margin: 0; padding-top: var(--space-md); border-top: 2px solid var(--color-ink); }
.stat-row dt { color: var(--color-ink-soft); font-size: var(--text-xs); font-weight: 600; }
.stat-row dd { margin: var(--space-2xs) 0 0; font-family: var(--font-display); font-size: clamp(1.7rem, 2.4vw, 2.3rem); font-weight: 600; letter-spacing: -0.03em; line-height: 1; }
.stat-row dd small { font-size: 0.5em; font-weight: 600; color: var(--color-muted); }
.teachers__note { max-width: 40rem; color: var(--color-ink-soft); font-size: var(--text-sm); line-height: 1.6; }

.architecture { padding: var(--space-xl) var(--page-gutter) var(--space-3xl); background: var(--color-night); color: var(--color-night-text); }
.architecture > * { width: min(100%, var(--content-max)); margin: 0 auto; }
.architecture__copy { display: grid; justify-items: center; gap: var(--space-lg); text-align: center; }
.architecture__copy h2 { max-width: 34ch; margin-inline: auto; font-size: var(--text-2xl); font-weight: 600; }
.architecture__copy > p:not(.eyebrow) { max-width: 42rem; margin-inline: auto; color: color-mix(in oklch, var(--color-night-text) 73%, transparent); font-size: var(--text-lg); line-height: 1.65; }
.eyebrow--light { color: color-mix(in oklch, var(--color-night-text) 72%, transparent); }
.text-link--light { color: var(--color-night-text); }
.architecture__map { display: grid; gap: var(--space-sm); margin-top: var(--space-xl); }
.architecture__node { display: grid; gap: var(--space-sm); padding: var(--space-lg); border: var(--rule-hair) solid color-mix(in oklch, var(--color-night-text) 20%, transparent); border-radius: var(--radius-md); background: color-mix(in oklch, var(--color-night-text) 7%, transparent); backdrop-filter: blur(1rem); }
.architecture__node span { display: block; color: var(--color-accent-night); font-family: var(--font-mono); font-size: var(--text-xs); font-weight: 700; }
.architecture__node b { display: block; font-family: var(--font-display); font-weight: 600; font-size: 1.15rem; letter-spacing: -0.02em; line-height: 1.2; text-wrap: balance; }
.architecture__node p { max-width: 26rem; color: color-mix(in oklch, var(--color-night-text) 66%, transparent); font-size: var(--text-sm); line-height: 1.55; }
.architecture__node code { padding-top: var(--space-sm); border-top: var(--rule-hair) solid color-mix(in oklch, var(--color-night-text) 20%, transparent); font-family: var(--font-mono); font-size: 0.72rem; color: color-mix(in oklch, var(--color-night-text) 55%, transparent); }
.architecture__node--core { border-color: color-mix(in oklch, var(--color-accent-night) 54%, transparent); background: color-mix(in oklch, var(--color-accent-night) 18%, transparent); }
.architecture__node--core code { border-top-color: color-mix(in oklch, var(--color-accent-night) 40%, transparent); }
.architecture__line { height: 2.5rem; width: 1px; margin-left: var(--space-xl); background: color-mix(in oklch, var(--color-accent-night) 52%, transparent); }
.architecture__footnote { max-width: 42rem; margin: var(--space-xl) auto 0; color: color-mix(in oklch, var(--color-night-text) 60%, transparent); font-size: var(--text-sm); font-style: italic; line-height: 1.6; text-align: center; }

.roles__head { display: grid; gap: var(--space-lg); }
.role-list { margin-top: var(--space-xl); border-top: var(--rule-hair) solid var(--color-rule); }
.role-item { display: grid; gap: var(--space-md); padding: var(--space-xl) 0; border-bottom: var(--rule-hair) solid var(--color-rule); }
.role-item span { color: var(--color-accent); font-family: var(--font-body); font-size: var(--text-xs); font-weight: 700; text-transform: uppercase; }
.role-item h3 { max-width: 29rem; margin-top: var(--space-xs); font-size: clamp(1.4rem, 2.4vw, 2.2rem); font-weight: 600; }
.role-item > p { max-width: 31rem; color: var(--color-ink-soft); line-height: 1.6; }
.closing { width: min(100%, var(--content-max)); margin: 0 auto; padding: var(--space-3xl) var(--page-gutter); display: grid; justify-items: start; gap: var(--space-lg); }
.closing h2 { max-width: 15ch; }
.closing > p:not(.eyebrow) { max-width: 38rem; color: var(--color-ink-soft); font-size: var(--text-lg); line-height: 1.6; }

.footer { position: relative; overflow: clip; padding: var(--space-3xl) var(--page-gutter) 0; background: var(--color-night); color: var(--color-night-text); }
.footer__top { width: min(100%, var(--content-max)); margin: 0 auto; display: grid; gap: var(--space-2xl); }
.footer__brand { max-width: 34rem; display: grid; gap: var(--space-md); align-content: start; }
.brand--light { color: var(--color-night-text); }
.footer__brand > p { color: color-mix(in oklch, var(--color-night-text) 68%, transparent); font-size: var(--text-sm); line-height: 1.65; }
.footer__copy { color: color-mix(in oklch, var(--color-night-text) 48%, transparent) !important; }
.footer__nav { display: grid; gap: var(--space-xl); }
.footer__col { display: grid; gap: var(--space-sm); align-content: start; }
.footer__col h2 { font-family: var(--font-display); font-size: var(--text-sm); font-weight: 600; letter-spacing: 0; }
.footer__col a, .footer__link { justify-self: start; padding: 0; border: 0; background: transparent; color: color-mix(in oklch, var(--color-night-text) 68%, transparent); font-size: var(--text-sm); font-weight: 400; text-align: left; transition: color var(--dur-short) var(--ease-out); }
.footer__wordmark { position: relative; margin: var(--space-2xl) 0 0; font-family: var(--font-display); font-size: clamp(5rem, 21vw, 19rem); font-weight: 700; letter-spacing: -0.045em; line-height: 0.78; text-align: center; color: transparent; background: linear-gradient(180deg, color-mix(in oklch, var(--color-accent-night) 34%, transparent) 0%, transparent 88%); background-clip: text; -webkit-background-clip: text; user-select: none; }

.demo-dialog { width: min(calc(100% - 2rem), 39rem); padding: var(--space-xl); border: var(--rule-hair) solid var(--color-rule); border-radius: var(--radius-lg); background: var(--color-paper-raised); color: var(--color-ink); box-shadow: var(--shadow-glass); backdrop-filter: blur(1.5rem) saturate(1.2); }
.demo-dialog::backdrop { background: color-mix(in oklch, var(--color-night) 35%, transparent); backdrop-filter: blur(0.3rem); }
.dialog-close { position: absolute; top: var(--space-md); right: var(--space-md); width: 2.75rem; height: 2.75rem; border: var(--rule-hair) solid var(--color-rule); border-radius: 50%; background: var(--color-paper-raised); color: var(--color-ink); font-size: 1.6rem; line-height: 1; }
.dialog-copy { display: grid; gap: var(--space-lg); max-width: 31rem; padding-right: var(--space-xl); }
.dialog-copy h2 { font-size: var(--text-xl); font-weight: 600; }
.dialog-copy > p:not(.eyebrow) { color: var(--color-ink-soft); }
.demo-form { display: grid; gap: var(--space-md); margin-top: var(--space-xl); }
.demo-form label { display: grid; gap: var(--space-xs); color: var(--color-ink-soft); font-size: var(--text-sm); font-weight: 700; }
.demo-form input { min-height: 3rem; padding-inline: var(--space-sm); border: var(--rule-hair) solid var(--color-rule-strong); border-radius: var(--radius-sm); outline: 2px solid transparent; outline-offset: 1px; background: color-mix(in oklch, var(--color-paper) 76%, transparent); color: var(--color-ink); transition: background-color var(--dur-short) var(--ease-out); }
.demo-form input::placeholder { color: var(--color-muted); }
.demo-form input:focus-visible { outline-color: var(--color-focus); }
.demo-form input[aria-invalid="true"] { border-color: var(--color-error); }
.form-message { min-height: 1.5lh; color: var(--color-muted); font-size: var(--text-sm); }
.form-message.is-error { color: var(--color-error); }
.form-message.is-success { color: var(--color-success); }

[data-reveal] { opacity: 0; transform: translateY(0.7rem); transition: opacity var(--dur-long) var(--ease-out), transform var(--dur-long) var(--ease-out); }
[data-reveal].is-visible { opacity: 1; transform: none; }
@media (hover: hover) and (pointer: fine) { .button:hover { background: var(--color-accent); border-color: var(--color-accent); color: var(--color-accent-ink); } .text-link:hover::after, .site-nav__links a:hover::after { transform: scaleX(1); } .exp-nav__btn:not(:disabled):hover { background: var(--color-accent); color: var(--color-accent-ink); border-color: var(--color-accent); } .demo-form input:hover { background: var(--color-paper-soft); } .footer__col a:hover, .footer__link:hover { color: var(--color-night-text); } }
@media (min-width: 40rem) { .site-nav__links { display: flex; } .nav-menu { display: none; } .button--nav { display: inline-flex; } .hero__actions { flex-wrap: nowrap; } .architecture__map { grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr) auto minmax(0, 1fr); align-items: stretch; } .architecture__line { width: 2.5rem; height: 1px; margin: 50% 0 0; } .architecture__node { padding: var(--space-xl); } .role-item { grid-template-columns: minmax(0, 1.4fr) minmax(0, 0.8fr); gap: var(--space-xl); } .footer__nav { grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--space-lg); } .teacher-tools { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
@media (min-width: 60rem) { .footer__top { grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr); gap: clamp(3rem, 8vw, 8rem); } .exp-card { width: calc((var(--visible-w) - var(--space-lg)) / 1.5); } .method__steps { grid-template-columns: repeat(3, minmax(0, 1fr)); } .method__steps li { grid-row: span 3; grid-template-rows: subgrid; } .chat-steps { grid-template-columns: repeat(2, minmax(0, 1fr)); } .chat-steps li { grid-row: span 4; grid-template-rows: subgrid; } .teachers__body { grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr); gap: clamp(2.5rem, 5vw, 4.5rem); } }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { scroll-behavior: auto !important; animation-duration: 1ms !important; animation-iteration-count: 1 !important; transition-duration: 1ms !important; } [data-reveal] { opacity: 1; transform: none; } .mini-pop { opacity: 1; transform: none; animation: none !important; } .mini-toggle__thumb, .mini-toggle__opt, .flip-card, .mode-reply__a, .mode-reply__b { animation: none !important; } .mini-toggle__opt:nth-of-type(1) { color: white; } .mini-toggle__opt:nth-of-type(2) { color: var(--color-ink-soft); } .mode-reply__b { opacity: 0; } }

.architecture {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: clamp(4.5rem, 7vw, 7rem) var(--page-gutter) clamp(4rem, 6vw, 6rem);
  background: var(--color-night);
  color: var(--color-night-text);
  text-align: center;
}

.architecture > * {
  width: min(100%, var(--content-max));
  margin-inline: auto;
}

.architecture__copy {
  display: grid;
  justify-items: center;
  gap: clamp(1.1rem, 1.8vw, 1.5rem);
  width: min(100%, 68rem);
  margin-bottom: clamp(2.75rem, 4.5vw, 4rem);
}

.architecture__copy h2 {
  max-width: 22ch;
  margin: 0;
  font-size: clamp(2.7rem, 5.2vw, 5.6rem);
  font-weight: 600;
  letter-spacing: -0.065em;
  line-height: 0.98;
  text-wrap: balance;
}

.architecture__copy > p:not(.eyebrow) {
  max-width: 43rem;
  margin: 0;
  color: color-mix(in oklch, var(--color-night-text) 73%, transparent);
  font-size: clamp(1rem, 1.35vw, 1.18rem);
  line-height: 1.55;
  text-wrap: balance;
}

.architecture__map {
  display: grid;
  grid-template-columns: minmax(0, 1fr) clamp(1.5rem, 3vw, 2.75rem) minmax(0, 1fr) clamp(1.5rem, 3vw, 2.75rem) minmax(0, 1fr);
  align-items: stretch;
  width: min(100%, 86rem);
  margin: 0 auto;
  text-align: left;
}

.architecture__node {
  display: flex;
  flex-direction: column;
  min-height: 15.25rem;
  padding: clamp(1.5rem, 2.2vw, 2rem);
  border: var(--rule-hair) solid color-mix(in oklch, var(--color-night-text) 20%, transparent);
  border-radius: var(--radius-md);
  background: color-mix(in oklch, var(--color-night-text) 7%, transparent);
  backdrop-filter: blur(1rem);
  -webkit-backdrop-filter: blur(1rem);
}

.architecture__node span {
  display: block;
  margin-bottom: 1.2rem;
  color: var(--color-accent-night);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-weight: 700;
}

.architecture__node b {
  display: block;
  color: var(--color-night-text);
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
  letter-spacing: -0.025em;
  line-height: 1.2;
  text-wrap: balance;
}

.architecture__node p {
  max-width: none;
  margin: 0.85rem 0 1rem;
  color: color-mix(in oklch, var(--color-night-text) 66%, transparent);
  font-size: var(--text-sm);
  line-height: 1.5;
}

.architecture__node code {
  display: block;
  margin-top: auto;
  padding-top: 1rem;
  border-top: var(--rule-hair) solid color-mix(in oklch, var(--color-night-text) 20%, transparent);
  color: color-mix(in oklch, var(--color-night-text) 58%, transparent);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  line-height: 1.4;
  white-space: normal;
}

.architecture__node--core {
  border-color: color-mix(in oklch, var(--color-accent-night) 54%, transparent);
  background: color-mix(in oklch, var(--color-accent-night) 18%, transparent);
}

.architecture__node--core code {
  border-top-color: color-mix(in oklch, var(--color-accent-night) 40%, transparent);
}

.architecture__line {
  align-self: start;
  width: 100%;
  height: 1px;
  margin: 1.15rem 0 0;
  background: color-mix(in oklch, var(--color-accent-night) 52%, transparent);
}

.architecture__footnote {
  width: min(100%, 46rem);
  margin: clamp(1.75rem, 3vw, 2.5rem) auto 0;
  color: color-mix(in oklch, var(--color-night-text) 60%, transparent);
  font-size: var(--text-sm);
  font-style: italic;
  line-height: 1.5;
  text-align: center;
  text-wrap: balance;
}

@media (max-width: 39.99rem) {
  .architecture { padding-block: 4rem; }
  .architecture__copy { margin-bottom: 2.5rem; }
  .architecture__copy h2 { max-width: 14ch; letter-spacing: -0.055em; line-height: 1.02; }
  .architecture__map { grid-template-columns: 1fr; gap: var(--space-sm); width: min(100%, 34rem); }
  .architecture__line { display: none; }
  .architecture__node { min-height: auto; }
}

@media (min-width: 40rem) {
  .architecture__map {
    grid-template-columns: minmax(0, 1fr) clamp(1.5rem, 3vw, 2.75rem) minmax(0, 1fr) clamp(1.5rem, 3vw, 2.75rem) minmax(0, 1fr);
    align-items: stretch;
  }

  .architecture__line {
    display: block;
    align-self: start;
    width: 100%;
    height: 1px;
    margin: 1.15rem 0 0;
  }

  .architecture__node { padding: clamp(1.5rem, 2.2vw, 2rem); }
}