:root {
  color-scheme: light;

  /* Canonical light palette values and the semantic CSS bridge. */
  --color-bg-main: #F8FAFC;
  --color-bg-card: #FFFFFF;
  --color-bg-hover: #F1F5F9;
  --color-border: #E2E8F0;
  --color-text-main: #0F172A;
  --color-text-muted: #64748B;
  --color-text-inverse: #FFFFFF;
  --color-accent: #0369A1;
  --color-focus: #0369A1;

  --surface-canvas: var(--color-bg-main);
  --surface-panel: var(--color-bg-card);
  --surface-soft: var(--color-bg-hover);
  --content-primary: var(--color-text-main);
  --content-secondary: var(--color-text-muted);
  --content-inverse: var(--color-text-inverse);
  --action-primary: var(--color-accent);
  --action-focus: var(--color-focus);
  --border-subtle: var(--color-border);

  --font-sans: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --text-body: 1rem;
  --text-lead: 1.2rem;
  --text-label: 0.875rem;
  --text-brand: 1.125rem;
  --text-mark: 1rem;
  --text-h1: clamp(2.75rem, 7vw, 5.5rem);
  --text-h2: clamp(2rem, 4vw, 3.25rem);
  --text-h3: 1.25rem;
  --text-legal-title: clamp(2.5rem, 6vw, 4.5rem);
  --text-legal-section: clamp(1.5rem, 3vw, 2rem);
  --line-body: 1.65;
  --line-heading: 1.08;

  --space-1: 0.5rem;
  --space-2: 0.75rem;
  --space-3: 1rem;
  --space-4: 1.5rem;
  --space-5: 2rem;
  --space-6: 3rem;
  --space-7: 4.5rem;
  --space-8: 6rem;

  --radius-small: 0.75rem;
  --radius-medium: 1.25rem;
  --radius-large: 2rem;
  --content-width: 72rem;
  --reading-width: 48rem;
}

* { box-sizing: border-box; }

html {
  background: var(--surface-canvas);
  color: var(--content-primary);
  scroll-behavior: smooth;
  text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--surface-canvas);
  color: var(--content-primary);
  font-family: var(--font-sans);
  font-size: var(--text-body);
  line-height: var(--line-body);
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--action-primary);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

a:hover { text-decoration-thickness: 0.14em; }

a:focus-visible {
  outline: 2px solid var(--action-focus);
  outline-offset: 3px;
  border-radius: 0.2rem;
}

button, a { -webkit-tap-highlight-color: transparent; }

.shell {
  width: min(calc(100% - 2 * var(--space-4)), var(--content-width));
  margin-inline: auto;
}

.skip-link {
  position: absolute;
  z-index: 5;
  top: var(--space-2);
  left: var(--space-2);
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
  padding-inline: var(--space-3);
  transform: translateY(-160%);
  border: 2px solid var(--action-focus);
  border-radius: var(--radius-small);
  background: var(--surface-panel);
  color: var(--content-primary);
}

.skip-link:focus { transform: translateY(0); }

.site-header {
  display: flex;
  min-height: 5rem;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  padding-block: var(--space-2);
  border-bottom: 1px solid var(--border-subtle);
}

.brand {
  display: inline-flex;
  min-height: 2.75rem;
  flex: 0 0 auto;
  align-items: center;
  gap: var(--space-2);
  color: var(--content-primary);
  font-size: var(--text-brand);
  font-weight: 750;
  letter-spacing: -0.04em;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 2.25rem;
  height: 2.25rem;
  place-items: center;
  border-radius: var(--radius-small);
  background: var(--action-primary);
  color: var(--content-inverse);
  font-size: var(--text-mark);
  font-weight: 750;
  letter-spacing: -0.04em;
}

.site-nav, .footer-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-1);
}

.site-nav a, .footer-nav a {
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
  justify-content: center;
  padding-inline: var(--space-2);
  border-radius: var(--radius-small);
  color: var(--content-primary);
  font-size: var(--text-body);
  text-decoration: none;
}

.site-nav a:hover, .footer-nav a:hover { background: var(--surface-soft); }
.site-nav a[aria-current="page"] { color: var(--action-primary); font-weight: 650; }
.site-nav .nav-contact { color: var(--action-primary); }

.hero {
  display: grid;
  min-height: 37rem;
  grid-template-columns: minmax(0, 1.1fr) minmax(17rem, 0.9fr);
  align-items: center;
  gap: var(--space-6);
  padding-block: var(--space-7);
}

.hero-copy { max-width: 42rem; }
.eyebrow {
  margin: 0 0 var(--space-3);
  color: var(--action-primary);
  font-size: var(--text-label);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1, h2, h3, p { overflow-wrap: anywhere; }
h1, h2, h3 { color: var(--content-primary); line-height: var(--line-heading); }

h1 {
  max-width: 11ch;
  margin: 0;
  font-size: var(--text-h1);
  font-weight: 720;
  letter-spacing: -0.065em;
}

.hero-lead {
  max-width: 40rem;
  margin: var(--space-4) 0 0;
  color: var(--content-secondary);
  font-size: var(--text-lead);
  line-height: 1.55;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-3) var(--space-4);
  margin-top: var(--space-5);
}

.button {
  display: inline-flex;
  min-height: 2.75rem;
  align-items: center;
  justify-content: center;
  padding: var(--space-2) var(--space-4);
  border: 2px solid transparent;
  border-radius: 999px;
  font-size: var(--text-body);
  font-weight: 650;
  text-align: center;
  text-decoration: none;
  transition: background-color 120ms ease, transform 120ms ease;
}

.button-primary { background: var(--action-primary); color: var(--content-inverse); }
.button-primary:hover { background: var(--content-primary); color: var(--content-inverse); }
.button:active { transform: translateY(1px); }
.text-link { display: inline-flex; min-height: 2.75rem; align-items: center; gap: var(--space-1); font-weight: 650; }
.quiet-note { margin: var(--space-3) 0 0; color: var(--content-secondary); font-size: var(--text-body); }

.hero-art {
  position: relative;
  display: grid;
  min-height: 22rem;
  place-items: center;
  isolation: isolate;
}

.envelope-card {
  display: grid;
  width: min(100%, 21rem);
  min-height: 17rem;
  place-items: center;
  padding: var(--space-4);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-large);
  background: var(--surface-panel);
  color: var(--action-primary);
}

.envelope { display: block; width: min(100%, 14rem); height: auto; }
.art-caption { margin-top: calc(-1 * var(--space-2)); color: var(--content-secondary); font-size: var(--text-body); font-weight: 600; }
.art-orbit { position: absolute; z-index: -1; border: 1px solid var(--border-subtle); border-radius: 50%; }
.art-orbit-one { width: min(21rem, 100%); aspect-ratio: 1; }
.art-orbit-two { width: min(28rem, 100%); aspect-ratio: 1; }
.art-dot { position: absolute; width: 1rem; height: 1rem; border: 3px solid var(--surface-canvas); border-radius: 50%; background: var(--action-primary); }
.art-dot-one { top: 16%; right: 15%; }
.art-dot-two { bottom: 18%; left: 12%; width: 0.7rem; height: 0.7rem; }

.intro-band, .platform-section { background: var(--surface-soft); }
.intro-band, .platform-section { --content-secondary: var(--content-primary); }
.intro-grid {
  display: grid;
  grid-template-columns: minmax(12rem, 0.65fr) minmax(0, 1.35fr);
  gap: var(--space-6);
  padding-block: var(--space-7);
}

h2 {
  max-width: 18ch;
  margin: 0;
  font-size: var(--text-h2);
  font-weight: 680;
  letter-spacing: -0.05em;
}

.intro-grid p:not(.eyebrow) {
  max-width: var(--reading-width);
  margin: var(--space-3) 0 0;
  color: var(--content-secondary);
  font-size: var(--text-lead);
}

.section { padding-block: var(--space-8); }
.section-heading { max-width: 45rem; margin-bottom: var(--space-6); }
.section-heading h2 { max-width: 22ch; }

.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--space-4);
}

.step {
  min-height: 15rem;
  padding: var(--space-4);
  border-top: 2px solid var(--action-primary);
  background: var(--surface-panel);
}

.step-number { margin: 0 0 var(--space-5); color: var(--content-secondary); font-variant-numeric: tabular-nums; }
h3 { margin: 0; font-size: var(--text-h3); font-weight: 680; letter-spacing: -0.025em; }
.step > p:last-child { margin: var(--space-3) 0 0; color: var(--content-secondary); }

.platform-layout {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(18rem, 1.1fr);
  gap: var(--space-7);
  align-items: start;
  padding-block: var(--space-7);
}

.platform-layout h2 { max-width: 14ch; }
.platform-list { display: grid; gap: var(--space-2); margin: 0; padding: 0; list-style: none; }
.platform-list li { display: flex; min-height: 5rem; align-items: center; gap: var(--space-3); padding: var(--space-2) 0; border-bottom: 1px solid var(--border-subtle); }
.platform-symbol { display: grid; min-width: 4.5rem; min-height: 2.75rem; place-items: center; padding-inline: var(--space-2); border: 1px solid var(--border-subtle); border-radius: var(--radius-small); background: var(--surface-panel); color: var(--action-primary); font-size: var(--text-label); font-weight: 700; }
.platform-list li > span:last-child { display: grid; gap: 0.15rem; }
.platform-list strong { font-size: var(--text-body); }
.platform-list li > span:last-child > span { color: var(--content-secondary); }

.closing-section { padding-block: var(--space-7); }
.closing-card { padding: clamp(var(--space-4), 6vw, var(--space-7)); border: 1px solid var(--border-subtle); border-radius: var(--radius-large); background: var(--surface-panel); }
.closing-card h2 { max-width: 18ch; }
.closing-card > p:not(.eyebrow) { max-width: 42rem; margin: var(--space-3) 0 0; color: var(--content-secondary); font-size: var(--text-lead); }

.legal-page { padding-block: var(--space-7) var(--space-8); }
.legal-heading { max-width: var(--reading-width); }
.legal-heading h1 { max-width: 13ch; font-size: var(--text-legal-title); }
.legal-heading > p:not(.eyebrow) { margin: var(--space-4) 0 0; color: var(--content-secondary); font-size: var(--text-lead); }
.legal-heading .legal-date { color: var(--content-primary); font-size: var(--text-body); font-weight: 650; }

.legal-toc {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  margin-block: var(--space-5) var(--space-6);
  padding-block: var(--space-2);
  border-block: 1px solid var(--border-subtle);
}

.legal-toc a { display: inline-flex; min-height: 2.75rem; align-items: center; padding-inline: var(--space-2); border-radius: var(--radius-small); }
.legal-content { max-width: var(--reading-width); }
.legal-content section { padding-block: var(--space-4); border-bottom: 1px solid var(--border-subtle); scroll-margin-top: var(--space-4); }
.legal-content h2 { max-width: none; margin-bottom: var(--space-3); font-size: var(--text-legal-section); letter-spacing: -0.035em; }
.legal-content p { margin: 0 0 var(--space-3); }
.legal-content p:last-child { margin-bottom: 0; }
.legal-content ul { margin: var(--space-2) 0 var(--space-3); padding-left: 1.4em; }
.legal-content li { padding-left: var(--space-1); margin-block: var(--space-1); }
.back-link { margin: var(--space-5) 0 0; }
.back-link a { display: inline-flex; min-height: 2.75rem; align-items: center; }

.site-footer { margin-top: var(--space-6); border-top: 1px solid var(--border-subtle); background: var(--surface-panel); }
.footer-content { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2) var(--space-4); padding-block: var(--space-4); }
.footer-brand { font-size: var(--text-body); }
.footer-content > p { margin: 0; color: var(--content-secondary); }
.footer-nav { margin-left: auto; }
.footer-nav a { font-size: var(--text-body); }
.footer-note { flex: 1 0 100%; font-size: var(--text-body); }

@media (max-width: 56rem) {
  .hero { grid-template-columns: minmax(0, 1fr) minmax(14rem, 0.75fr); gap: var(--space-4); }
  .hero-art { min-height: 18rem; }
  .art-orbit-one { width: min(17rem, 100%); }
  .art-orbit-two { width: min(23rem, 100%); }
  .intro-grid, .platform-layout { grid-template-columns: minmax(0, 1fr); gap: var(--space-4); }
}

@media (max-width: 42rem) {
  .shell { width: min(calc(100% - 2 * var(--space-3)), var(--content-width)); }
  .site-header { align-items: flex-start; flex-direction: column; padding-block: var(--space-2); }
  .site-nav { width: 100%; justify-content: flex-start; }
  .site-nav a { padding-inline: var(--space-2); }
  .hero { min-height: 0; grid-template-columns: minmax(0, 1fr); padding-block: var(--space-6); }
  .hero-copy { max-width: none; }
  .hero-art { min-height: 15rem; }
  .envelope-card { min-height: 13rem; }
  .envelope { width: min(100%, 11rem); }
  .art-orbit-one { width: min(14rem, 100%); }
  .art-orbit-two { width: min(19rem, 100%); }
  .intro-grid, .section, .platform-layout, .closing-section, .legal-page { padding-block: var(--space-6); }
  .steps { grid-template-columns: minmax(0, 1fr); }
  .step { min-height: auto; }
  .step-number { margin-bottom: var(--space-3); }
  .footer-nav { width: 100%; margin-left: 0; }
  .footer-content { align-items: flex-start; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; }
}

@font-face {
  font-family: Geist;
  src: url("fonts/Geist-Variable.woff2") format("woff2");
  font-style: normal;
  font-weight: 100 900;
  font-display: swap;
}

:root {
  --font-sans: Geist, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --color-accent-ink: var(--color-accent);
  --color-accent-soft: color-mix(in srgb, var(--color-accent) 12%, var(--color-bg-card));
  --color-paper-warm: var(--color-bg-hover);
  --color-paper-sage: var(--color-bg-hover);
  --color-deep-ink: var(--color-text-main);
  --color-line: var(--color-border);
  --color-white: var(--color-bg-card);
}

body { background: var(--surface-canvas); }
.site-header { min-height: 5.25rem; border-bottom-color: transparent; }
.brand { font-weight: 650; letter-spacing: -0.045em; }
.brand-mark { border-radius: 50%; background: var(--color-accent-ink); }
.site-nav a { font-size: var(--text-label); font-weight: 550; }
.site-nav .nav-contact { padding-inline: 1.1rem; border: 1px solid var(--border-subtle); border-radius: 999px; }
.site-nav .nav-contact:hover { background: var(--surface-panel); }

.hero {
  min-height: 42rem;
  grid-template-columns: minmax(0, 1.04fr) minmax(20rem, 0.96fr);
  gap: var(--space-6);
  padding-block: 3.5rem 5rem;
}
.hero-copy { position: relative; z-index: 1; }
.eyebrow { margin-bottom: 1.1rem; color: var(--color-accent-ink); font-size: 0.875rem; letter-spacing: 0.12em; }
h1 { max-width: 10ch; font-size: clamp(3.6rem, 7.1vw, 6.7rem); font-weight: 580; letter-spacing: -0.083em; line-height: 0.96; }
h1 em { color: var(--color-accent-ink); font-style: normal; }
.hero-lead { max-width: 36rem; color: var(--content-secondary); font-size: clamp(1.1rem, 1.5vw, 1.28rem); line-height: 1.55; }
.hero-actions { gap: var(--space-3) var(--space-4); }
.button-primary { background: var(--color-accent-ink); }
.button-primary:hover { background: var(--color-deep-ink); }
.button { transition: background-color 160ms ease, transform 160ms ease; }
.text-link { color: var(--color-accent-ink); text-underline-offset: 0.25em; }
.quiet-note { display: flex; align-items: center; gap: 0.55rem; color: var(--content-secondary); font-size: var(--text-label); }
.note-mark { color: var(--color-accent-ink); font-size: 1.15rem; }

.hero-art {
  min-height: 32rem;
  overflow: visible;
  border-radius: 0;
  background: transparent;
}
.art-wash { position: absolute; z-index: -1; width: 96%; aspect-ratio: 1; border: 0; border-radius: 50%; background: radial-gradient(ellipse at 53% 48%, var(--color-bg-card) 0 18%, color-mix(in srgb, var(--color-bg-hover) 70%, var(--color-accent-soft)) 57%, var(--color-bg-hover) 100%); }
.orbit { position: absolute; z-index: -1; width: 86%; aspect-ratio: 1; border: 1px solid color-mix(in srgb, var(--color-accent) 12%, transparent); border-radius: 50%; }
.orbit-b { width: 106%; max-width: 100%; }
.mail-piece, .group-card { position: absolute; display: flex; align-items: center; gap: 0.75rem; border: 1px solid color-mix(in srgb, var(--color-text-main) 8%, transparent); background: color-mix(in srgb, var(--color-bg-card) 94%, transparent); box-shadow: 0 18px 42px color-mix(in srgb, var(--color-text-main) 10%, transparent); }
.mail-piece { z-index: 1; width: min(16rem, 55%); min-height: 4.5rem; padding: 0.65rem 0.8rem; border-left: 3px solid var(--color-accent); border-radius: 1rem; }
.mail-piece b, .group-card b { display: block; color: var(--color-deep-ink); font-size: 0.88rem; font-weight: 620; }
.mail-piece small, .group-card small { display: block; color: var(--content-secondary); font-size: 0.875rem; }
.piece-icon { display: grid; width: 2.3rem; height: 2.3rem; flex: 0 0 auto; place-items: center; border-radius: 50%; background: var(--color-accent-soft); color: var(--color-accent-ink); font-weight: 700; }
.icon-gold { background: var(--color-paper-warm); color: var(--color-text-main); }
.icon-sage { background: var(--color-paper-sage); color: var(--color-text-main); }
.mail-piece i { width: 0.48rem; height: 0.48rem; margin-left: auto; border-radius: 50%; background: var(--color-accent-ink); }
.piece-one { top: 18%; left: 8%; transform: rotate(-7deg); animation: drift-one 5.8s ease-in-out infinite; }
.piece-two { top: 39%; right: 4%; transform: rotate(5deg); animation: drift-two 6.5s ease-in-out infinite; }
.piece-three { bottom: 21%; left: 9%; transform: rotate(4deg); animation: drift-three 6s ease-in-out infinite; }
.group-card { z-index: 1; right: 9%; bottom: 14%; width: min(17rem, 65%); min-height: 5rem; padding: 0.8rem 1rem; border-left: 3px solid var(--color-accent); border-radius: 1.1rem; animation: group-arrive 6.2s ease-in-out infinite; }
.piece-one, .piece-two, .piece-three, .group-card { animation-play-state: paused; }
.hero-art[data-motion-state="running"] .piece-one, .hero-art[data-motion-state="running"] .piece-two, .hero-art[data-motion-state="running"] .piece-three, .hero-art[data-motion-state="running"] .group-card { animation-play-state: running; }
.group-icon { display: grid; width: 2.5rem; height: 2.5rem; place-items: center; border-radius: 0.8rem; background: var(--color-accent-ink); color: var(--color-text-inverse); }
.group-count { display: grid; width: 2rem; height: 2rem; margin-left: auto; place-items: center; border-radius: 50%; background: var(--color-accent-soft); color: var(--color-accent-ink); font-size: 0.875rem; font-weight: 700; }
.art-label { position: absolute; right: 0; bottom: -1.75rem; left: 0; margin: 0; color: var(--content-secondary); font-size: var(--text-label); text-align: center; }
.mail-scene { position: absolute; inset: 0; z-index: 0; width: 100%; height: 100%; opacity: 0; transition: opacity 600ms ease; }
.webgl-ready .mail-scene { opacity: 0.72; }
.webgl-ready .orbit, .webgl-ready .art-wash { opacity: 0.48; }
.motion-toggle { position: absolute; z-index: 2; top: 1rem; right: 1rem; min-height: 2.75rem; padding: 0.5rem 0.8rem; border: 1px solid var(--color-line); border-radius: 999px; background: var(--color-white); color: var(--color-deep-ink); font: inherit; font-size: 0.875rem; cursor: pointer; }
.motion-toggle[hidden] { display: none; }
.motion-toggle:hover { background: var(--surface-soft); }
.motion-toggle:focus-visible { outline: 2px solid var(--action-focus); outline-offset: 3px; }

.intro-band { --content-secondary: var(--content-primary); border-block: 1px solid var(--color-line); background: var(--surface-soft); }
.intro-grid { grid-template-columns: minmax(11rem, 0.6fr) minmax(0, 1.4fr); gap: var(--space-7); padding-block: 5.5rem; }
.intro-grid h2, .demo-heading h2, .future-grid h2, .platform-layout h2, .closing-card h2 { font-size: clamp(2.2rem, 4vw, 3.6rem); font-weight: 570; letter-spacing: -0.065em; line-height: 1.05; }
.intro-grid h2 { max-width: 17ch; }
.intro-grid p:not(.eyebrow) { max-width: 43rem; color: var(--content-secondary); font-size: 1.08rem; }

.demo-section { padding-block: 7.5rem; }
.demo-heading { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(15rem, 0.65fr); gap: var(--space-6); align-items: end; margin-bottom: var(--space-5); }
.demo-heading h2 { max-width: 16ch; }
.demo-heading > p { max-width: 27rem; margin: 0 0 0.3rem; color: var(--content-secondary); }
.demo { --content-secondary: var(--content-primary); overflow: hidden; border: 1px solid var(--color-line); border-radius: 1.5rem; background: var(--surface-soft); box-shadow: 0 24px 70px color-mix(in srgb, var(--color-text-main) 8%, transparent); }
.demo-tabs { display: flex; flex-wrap: wrap; gap: 0.4rem; margin: 0; padding: 1rem 1.15rem; border: 0; border-bottom: 1px solid var(--color-line); }
.demo-tabs legend { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; clip-path: inset(50%); }
.demo-tabs input { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); }
.demo-tabs label { display: inline-flex; min-height: 2.75rem; align-items: center; gap: 0.5rem; padding: 0.45rem 0.9rem; border: 1px solid transparent; border-radius: 999px; color: var(--content-secondary); font-size: var(--text-label); cursor: pointer; }
.demo-tabs label span { color: var(--content-secondary); font-size: 0.875rem; }
.demo-tabs input:checked + label { border-color: var(--color-line); background: var(--color-white); color: var(--color-deep-ink); font-weight: 650; }
.demo-tabs input:focus-visible + label { outline: 2px solid var(--action-focus); outline-offset: 2px; }
.demo-screen { min-height: 20rem; margin: 1rem; overflow: hidden; border: 1px solid var(--color-line); border-radius: 1rem; background: var(--color-white); }
.demo-topline { display: flex; min-height: 2.75rem; align-items: center; justify-content: space-between; gap: 0.5rem; padding-inline: 1rem; border-bottom: 1px solid var(--color-line); color: var(--content-secondary); font-size: 0.875rem; font-weight: 650; letter-spacing: 0.08em; }
.demo-lights { display: inline-flex; gap: 0.28rem; }
.demo-lights i { width: 0.42rem; height: 0.42rem; border-radius: 50%; background: var(--color-border); }
.demo-local { color: var(--color-accent-ink); }
.demo-content { display: none; min-height: 17rem; align-items: center; gap: var(--space-5); padding: clamp(1rem, 4vw, 2.3rem); }
.demo-tabs:has(#mode-tag:checked) + .demo-screen .demo-understand, .demo-tabs:has(#mode-sort:checked) + .demo-screen .demo-organize, .demo-tabs:has(#mode-learn:checked) + .demo-screen .demo-learning { display: flex; }
.demo-mail { display: grid; flex: 1 1 55%; grid-template-columns: 2.7rem minmax(0, 1fr) auto; align-items: center; gap: 0.75rem; }
.sender-avatar { display: grid; width: 2.6rem; height: 2.6rem; grid-row: span 2; place-items: center; border-radius: 50%; background: var(--color-paper-warm); color: var(--color-text-main); font-weight: 700; }
.demo-mail strong, .demo-mail small { display: block; }
.demo-mail strong { font-size: 0.93rem; }
.demo-mail small { color: var(--content-secondary); font-size: 0.875rem; }
.message-type { color: var(--color-accent-ink); font-size: 0.875rem; font-weight: 700; letter-spacing: 0.11em; }
.demo-mail h3 { grid-column: 2 / 4; margin-top: 0.8rem; font-size: 1.35rem; font-weight: 600; letter-spacing: -0.035em; }
.demo-mail p { grid-column: 2 / 4; max-width: 39rem; margin: 0.1rem 0 0; color: var(--content-secondary); font-size: 0.92rem; }
.ai-note { display: flex; flex: 0 1 18rem; align-items: flex-start; gap: 0.75rem; padding: 1.1rem; border: 1px solid var(--color-line); border-radius: 1rem; background: var(--surface-soft); }
.ai-spark { color: var(--color-accent-ink); font-size: 1.2rem; }
.ai-note b { font-size: 0.875rem; }
.ai-note p { margin: 0.35rem 0 0.55rem; color: var(--content-primary); font-size: 0.88rem; }
.ai-note small { color: var(--content-secondary); font-size: 0.875rem; }
.organize-intro { display: flex; align-items: center; justify-content: space-between; gap: 1rem; margin-bottom: 0.8rem; }
.organize-intro h3, .learning-copy h3 { margin-top: 0.35rem; font-size: 1.35rem; font-weight: 600; letter-spacing: -0.04em; }
.review-pill { padding: 0.4rem 0.65rem; border-radius: 999px; background: var(--color-paper-sage); color: var(--content-primary); font-size: 0.875rem; }
.sort-row { display: flex; min-height: 3.5rem; align-items: center; gap: 0.7rem; border-top: 1px solid var(--color-line); }
.sort-symbol { display: grid; width: 2rem; height: 2rem; place-items: center; border-radius: 0.6rem; background: var(--color-paper-warm); color: var(--color-text-main); }
.symbol-blue { background: var(--color-accent-soft); color: var(--color-accent-ink); }
.symbol-sage { background: var(--color-paper-sage); color: var(--color-text-main); }
.sort-row > span:nth-child(2) { display: grid; gap: 0.1rem; }
.sort-row b { font-size: 0.875rem; font-weight: 600; }
.sort-row small { color: var(--content-secondary); font-size: 0.875rem; }
.sort-action { margin-left: auto; color: var(--color-accent-ink); font-size: 0.875rem; font-weight: 650; }
.demo-footnote { margin: 0.7rem 0 0; color: var(--content-secondary); font-size: 0.875rem; }
.demo-learning { justify-content: space-between; }
.learning-copy { max-width: 32rem; }
.learning-copy h3 { max-width: 22ch; font-size: clamp(1.3rem, 2.4vw, 1.8rem); }
.learning-copy > p { max-width: 34rem; color: var(--content-secondary); font-size: 0.92rem; }
.learn-state { display: inline-flex; align-items: center; gap: 0.45rem; color: var(--color-text-main); font-size: 0.875rem; }
.learn-state i { width: 0.5rem; height: 0.5rem; border-radius: 50%; background: var(--color-accent); }
.choice-card { width: min(17rem, 38%); padding: 1rem; border: 1px solid var(--color-line); border-radius: 1rem; background: var(--color-bg-main); box-shadow: 0 12px 32px color-mix(in srgb, var(--color-text-main) 6%, transparent); }
.choice-card > small { display: block; color: var(--content-secondary); font-size: 0.875rem; letter-spacing: 0.1em; }
.choice-card > b { display: block; margin-block: 0.45rem 0.35rem; font-size: 0.9rem; }
.choice-card > p { margin: 0 0 0.8rem; color: var(--content-secondary); font-size: 0.875rem; }
.choice-options { display: grid; gap: 0.4rem; }
.choice-options span { display: flex; min-height: 2.75rem; align-items: center; justify-content: space-between; padding-inline: 0.6rem; border: 1px solid var(--color-line); border-radius: 0.65rem; color: var(--content-secondary); font-size: 0.875rem; }
.choice-options span:first-child { border-color: var(--color-line); background: var(--surface-soft); color: var(--content-primary); }
.demo-caption { margin: 0; padding: 0 1.3rem 1.1rem; color: var(--content-secondary); font-size: 0.875rem; }

.future-section { --content-secondary: var(--content-primary); padding-block: 6rem; background: var(--surface-soft); }
.future-grid { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr); gap: var(--space-7); }
.future-grid h2 { max-width: 13ch; }
.future-copy > p { max-width: 43rem; color: var(--content-primary); font-size: 1.02rem; }
.future-copy .text-link { margin-top: 0.6rem; }
.platform-section { background: var(--color-deep-ink); color: var(--color-text-inverse); }
.platform-section { --content-secondary: color-mix(in srgb, var(--color-text-inverse) 80%, transparent); }
.platform-layout { padding-block: 5.5rem; }
.platform-layout h2 { max-width: 14ch; color: var(--color-text-inverse); }
.platform-section .eyebrow { color: color-mix(in srgb, var(--color-text-inverse) 82%, var(--color-accent)); }
.platform-list li { border-color: color-mix(in srgb, var(--color-text-inverse) 18%, transparent); }
.platform-list strong { color: var(--color-text-inverse); }
.platform-symbol { border-color: color-mix(in srgb, var(--color-text-inverse) 20%, transparent); background: color-mix(in srgb, var(--color-text-inverse) 7%, transparent); color: var(--color-text-inverse); }
.closing-section { padding-block: 5.5rem; }
.closing-card { --content-secondary: var(--content-primary); padding: clamp(1.5rem, 5vw, 4rem); border-color: var(--color-line); border-radius: 1.5rem; background: var(--surface-soft); }
.closing-card h2 { max-width: 15ch; }
.closing-card > p:not(.eyebrow) { color: var(--content-secondary); }
.site-footer { margin-top: 0; border-color: var(--color-line); background: var(--color-white); }
.footer-brand .brand-mark { width: 1.8rem; height: 1.8rem; }
.footer-content > p, .footer-nav a { font-size: var(--text-label); }

@keyframes drift-one { 50% { transform: translate(0.3rem, -0.35rem) rotate(-5deg); } }
@keyframes drift-two { 50% { transform: translate(-0.25rem, 0.25rem) rotate(3deg); } }
@keyframes drift-three { 50% { transform: translate(0.2rem, 0.3rem) rotate(6deg); } }
@keyframes group-arrive { 0%, 100% { transform: translateY(0) scale(1); } 50% { transform: translateY(-0.3rem) scale(1.015); } }

@media (max-width: 56rem) {
  .hero { grid-template-columns: minmax(0, 1fr) minmax(17rem, 0.85fr); gap: var(--space-4); }
  .hero-art { min-height: 26rem; }
  .intro-grid { grid-template-columns: minmax(0, 1fr); gap: var(--space-3); }
  .intro-grid .eyebrow { margin-bottom: 0; }
}
@media (max-width: 42rem) {
  .site-header { align-items: center; flex-direction: row; }
  .site-nav { width: auto; flex-wrap: wrap; justify-content: flex-end; gap: 0; }
  .site-nav a { min-height: 2.75rem; padding-inline: 0.55rem; font-size: 0.875rem; }
  .site-nav .nav-contact { padding-inline: 0.7rem; }
  .hero { min-height: 0; grid-template-columns: minmax(0, 1fr); padding-block: 3rem 3.5rem; }
  h1 { max-width: 9ch; font-size: clamp(3.55rem, 15vw, 5rem); }
  .hero-art { min-height: min(95vw, 27rem); margin: 0.75rem -0.3rem 1.5rem; }
  .mail-piece { width: min(15rem, 62%); }
  .piece-one { left: 2%; }
  .piece-two { right: 1%; }
  .piece-three { left: 2%; }
  .group-card { right: 3%; width: min(16rem, 68%); }
  .intro-grid, .demo-section, .platform-layout, .closing-section { padding-block: 4rem; }
  .demo-heading, .future-grid { grid-template-columns: minmax(0, 1fr); gap: var(--space-3); }
  .demo-heading { margin-bottom: var(--space-4); }
  .demo-tabs { gap: 0.15rem; padding: 0.65rem; }
  .demo-tabs label { min-height: 2.75rem; padding-inline: 0.6rem; font-size: 0.875rem; }
  .demo-tabs label span { display: none; }
  .demo-screen { margin: 0.6rem; }
  .demo-content { flex-direction: column; align-items: stretch; gap: var(--space-3); padding: 1rem; }
  .demo-mail { grid-template-columns: 2.5rem minmax(0, 1fr); }
  .message-type { grid-column: 2; }
  .demo-mail h3, .demo-mail p { grid-column: 2; }
  .ai-note { flex-basis: auto; }
  .demo-learning { flex-direction: column; }
  .choice-card { width: 100%; }
  .demo-footnote { font-size: 0.875rem; }
  .future-section { padding-block: 4rem; }
  .platform-list { min-width: 0; }
  .footer-nav { width: auto; margin-left: auto; }
  .footer-content { gap: 0.5rem 1rem; }
}
@media (max-width: 22rem) {
  .shell { width: min(calc(100% - 1.5rem), var(--content-width)); }
  .site-nav a { padding-inline: 0.35rem; font-size: 0.875rem; }
  .brand { gap: 0.4rem; font-size: 1rem; }
  .brand-mark { width: 2rem; height: 2rem; }
  .hero-actions { align-items: flex-start; flex-direction: column; }
  .demo-tabs { flex-direction: column; align-items: stretch; }
  .demo-tabs label { justify-content: flex-start; }
  .demo-topline { padding-inline: 0.6rem; font-size: 0.875rem; }
  .demo-local { font-size: 0.875rem; }
}
@media (prefers-reduced-motion: reduce) {
  .piece-one, .piece-two, .piece-three, .group-card { animation: none; }
  .mail-scene { display: none; }
}