:root { --slide-w: 1920px; --slide-h: 1080px; }
  body { background: #060814; margin: 0; }
  @import url('https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500;700;900&family=Roboto+Mono:wght@400;500;600&family=Roboto+Flex:opsz,wght@8..144,300;8..144,400;8..144,500;8..144,700;8..144,900&display=swap');

  section {
    width: var(--slide-w); height: var(--slide-h);
    box-sizing: border-box; position: relative; overflow: hidden;
    display: flex; flex-direction: column;
    font-family: 'Roboto', system-ui, sans-serif;
    -webkit-font-smoothing: antialiased;
  }
  /* Page types */
  .pg-dark { background: #060814; color: #F5F7FF; padding: 96px 120px; }
  .pg-light { background: #FFFFFF; color: #0A2A56; padding: 96px 120px; }
  .pg-soft { background: #F5F8FE; color: #0A2A56; padding: 96px 120px; }
  .pg-blue { background: #1878F0; color: #fff; padding: 96px 120px; }

  /* Header bar */
  .pg-hdr { display: flex; justify-content: space-between; align-items: center; margin-bottom: 56px; }
  .pg-hdr-logo img { height: 28px; }
  .pg-hdr-sec { font-family: 'Roboto Mono', monospace; font-size: 13px; letter-spacing: .22em; text-transform: uppercase; opacity: .5; }
  .pg-dark .pg-hdr-sec { color: #8A93B8; }
  .pg-light .pg-hdr-sec, .pg-soft .pg-hdr-sec { color: #6B7794; }

  /* Footer */
  .pg-foot { position: absolute; bottom: 48px; left: 120px; right: 120px; display: flex; justify-content: space-between; font-family: 'Roboto Mono', monospace; font-size: 12px; }
  .pg-dark .pg-foot { color: #3B4677; }
  .pg-light .pg-foot, .pg-soft .pg-foot { color: #C5D2E8; }
  .pg-blue .pg-foot { color: rgba(255,255,255,.35); }

  /* Eyebrow */
  .ey { font-family: 'Roboto', sans-serif; font-weight: 700; font-size: 13px; letter-spacing: .28em; text-transform: uppercase; margin-bottom: 18px; display: inline-flex; align-items: center; gap: 12px; }
  .pg-dark .ey { color: #00C8F0; }
  .pg-light .ey, .pg-soft .ey { color: #1878F0; }
  .pg-blue .ey { color: rgba(255,255,255,.7); }
  .ey::before { content: ''; width: 24px; height: 1px; background: currentColor; }

  /* Headings */
  .h1 { font-family: 'Roboto Flex','Roboto', sans-serif; font-weight: 900; font-size: 72px; line-height: .95; letter-spacing: -.03em; }
  .h2 { font-family: 'Roboto Flex','Roboto', sans-serif; font-weight: 800; font-size: 56px; line-height: 1.0; letter-spacing: -.025em; }
  .h3 { font-family: 'Roboto Flex','Roboto', sans-serif; font-weight: 700; font-size: 36px; line-height: 1.1; letter-spacing: -.02em; }
  .h4 { font-family: 'Roboto', sans-serif; font-weight: 700; font-size: 22px; letter-spacing: -.01em; }
  .accent { color: #1878F0; }
  .pg-dark .accent { color: #00C8F0; }
  .pg-blue .accent { color: #fff; }

  /* Body */
  .lead { font-size: 22px; line-height: 1.5; font-weight: 400; max-width: 800px; margin-top: 22px; }
  .pg-dark .lead { color: #C2C9E4; }
  .pg-light .lead, .pg-soft .lead { color: #36456A; }
  .body { font-size: 17px; line-height: 1.6; max-width: 640px; }
  .pg-dark .body { color: #8A93B8; }
  .pg-light .body, .pg-soft .body { color: #6B7794; }
  .mono { font-family: 'Roboto Mono', monospace; }

  /* Grid helper */
  .flex { display: flex; }
  .gap-sm { gap: 14px; }
  .gap-md { gap: 24px; }
  .gap-lg { gap: 48px; }
  .gap-xl { gap: 80px; }
  .wrap { flex-wrap: wrap; }
  .grow { flex: 1; }
  .col { flex-direction: column; }
  .center { align-items: center; }
  .mid { justify-content: center; }
  .end { justify-content: flex-end; }
  .between { justify-content: space-between; }
  .grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
  .grid-3 { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 24px; }
  .grid-4 { display: grid; grid-template-columns: 1fr 1fr 1fr 1fr; gap: 18px; }
  .mt-auto { margin-top: auto; }

  /* Swatch */
  .sw { border-radius: 18px; padding: 16px; display: flex; flex-direction: column; justify-content: flex-end; min-height: 140px; }
  .sw .nm { font-weight: 700; font-size: 16px; }
  .sw .hx { font-family: 'Roboto Mono', monospace; font-size: 12px; opacity: .85; margin-top: 2px; }
  .sw .rl { font-family: 'Roboto Mono', monospace; font-size: 10px; letter-spacing: .16em; text-transform: uppercase; opacity: .7; margin-bottom: auto; }

  /* Rule callout */
  .rule { display: flex; gap: 18px; align-items: flex-start; padding: 20px 24px; border-radius: 16px; margin-top: 12px; }
  .pg-light .rule, .pg-soft .rule { background: #F5F8FE; border: 1px solid #EAF1FB; }
  .pg-dark .rule { background: rgba(255,255,255,.04); border: 1px solid #283264; }
  .rule-icon { width: 40px; height: 40px; border-radius: 12px; display: grid; place-items: center; flex-shrink: 0; font-size: 18px; font-weight: 900; }
  .rule-ok .rule-icon { background: #E5F8EF; color: #1FB877; }
  .rule-no .rule-icon { background: #FCE6E9; color: #E5394F; }
  .rule-info .rule-icon { background: #EAF1FB; color: #1878F0; }
  .rule-text { font-size: 15px; line-height: 1.5; }
  .rule-text strong { display: block; font-size: 14px; margin-bottom: 2px; }

  /* Card surface */
  .card-s { background: #fff; border: 1px solid #EAF1FB; border-radius: 20px; padding: 28px; box-shadow: 0 12px 32px -12px rgba(10,42,86,.10); }
  .pg-dark .card-s { background: #0F1530; border-color: #182148; box-shadow: 0 12px 32px -12px rgba(0,0,0,.5); }

  /* Tag */
  .tag { display: inline-flex; align-items: center; gap: 8px; padding: 5px 12px; border-radius: 999px; font-size: 11px; font-weight: 700; letter-spacing: .08em; }

  /* Aurora bg */
  .aurora-bg { position: absolute; inset: -10%; background: radial-gradient(40% 50% at 25% 35%, rgba(24,120,240,.55), transparent 60%), radial-gradient(50% 50% at 80% 25%, rgba(0,200,240,.4), transparent 60%), radial-gradient(55% 55% at 60% 95%, rgba(110,91,255,.55), transparent 60%); filter: blur(60px); pointer-events: none; }
  .grid-bg { position: absolute; inset: 0; background-image: linear-gradient(rgba(255,255,255,.04) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.04) 1px, transparent 1px); background-size: 80px 80px; mask-image: radial-gradient(70% 70% at 50% 50%, #000 30%, transparent 90%); pointer-events: none; }

  /* Mockup helpers */
  .mock-card { border-radius: 14px; overflow: hidden; box-shadow: 0 24px 60px -16px rgba(10,42,86,.25); }
  .mock-phone { width: 320px; height: 640px; border-radius: 44px; border: 8px solid #0A2A56; overflow: hidden; background: #fff; position: relative; }
  .mock-phone .notch { position: absolute; top: 0; left: 50%; transform: translateX(-50%); width: 120px; height: 28px; background: #0A2A56; border-radius: 0 0 18px 18px; z-index: 2; }
  .mock-laptop { width: 640px; border-radius: 12px 12px 0 0; border: 6px solid #0A2A56; border-bottom: 0; overflow: hidden; background: #fff; }
  .mock-laptop-base { width: 720px; height: 18px; background: #C5D2E8; border-radius: 0 0 8px 8px; margin-top: -1px; }