:root {
    --font-serif: "Charter", "Iowan Old Style", "Palatino Linotype", Georgia, serif;
    --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-mono: ui-monospace, "SF Mono", "Cascadia Code", Menlo, Consolas, monospace;
    --bg: #F4F7F1; --surface: #FFFFFF; --surface-2: #FBFCFA; --ink: #10231A;
    --body: #3C4E45; --muted: #6E8077; --line: #E2E9DF; --line-strong: #CFDAC9;
    --brand: #12B85C; --brand-press: #0E9C4D; --brand-ink: #0C6E38; --brand-bright: #17C964; --brand-wash: #E7F6EC;
    --shadow: 20px 40px 80px -40px rgba(16, 44, 30, 0.28);
    --shadow-sm: 0 1px 2px rgba(16, 44, 30, 0.05), 0 8px 24px -16px rgba(16, 44, 30, 0.18);
  }
  @media (prefers-color-scheme: dark) {
    :root {
      --bg: #0B1611; --surface: #111F18; --surface-2: #0F1C15; --ink: #E9F1EB;
      --body: #AFC1B6; --muted: #7C8F85; --line: #1E2C24; --line-strong: #294034;
      --brand: #24D46E; --brand-press: #17C964; --brand-ink: #6FE59B; --brand-bright: #2BE07A; --brand-wash: #12281C;
      --shadow: 20px 40px 90px -40px rgba(0,0,0,0.7);
      --shadow-sm: 0 1px 2px rgba(0,0,0,0.4), 0 10px 30px -18px rgba(0,0,0,0.6);
    }
  }
  :root[data-theme="light"] {
    --bg: #F4F7F1; --surface: #FFFFFF; --surface-2: #FBFCFA; --ink: #10231A;
    --body: #3C4E45; --muted: #6E8077; --line: #E2E9DF; --line-strong: #CFDAC9;
    --brand: #12B85C; --brand-press: #0E9C4D; --brand-ink: #0C6E38; --brand-bright: #17C964; --brand-wash: #E7F6EC;
    --shadow: 20px 40px 80px -40px rgba(16,44,30,0.28);
    --shadow-sm: 0 1px 2px rgba(16,44,30,0.05), 0 8px 24px -16px rgba(16,44,30,0.18);
  }
  :root[data-theme="dark"] {
    --bg: #0B1611; --surface: #111F18; --surface-2: #0F1C15; --ink: #E9F1EB;
    --body: #AFC1B6; --muted: #7C8F85; --line: #1E2C24; --line-strong: #294034;
    --brand: #24D46E; --brand-press: #17C964; --brand-ink: #6FE59B; --brand-bright: #2BE07A; --brand-wash: #12281C;
    --shadow: 20px 40px 90px -40px rgba(0,0,0,0.7);
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.4), 0 10px 30px -18px rgba(0,0,0,0.6);
  }

  * { box-sizing: border-box; }
  body { margin: 0; background: var(--bg); color: var(--body); font-family: var(--font-sans); font-size: 17px; line-height: 1.6; -webkit-font-smoothing: antialiased; text-rendering: optimizeLegibility; }
  ::selection { background: var(--brand-wash); color: var(--ink); }
  .wrap { max-width: 1120px; margin: 0 auto; padding: 0 28px; }

  h1, h2, h3 { font-family: var(--font-serif); color: var(--ink); font-weight: 600; text-wrap: balance; margin: 0; letter-spacing: -0.01em; }
  h1 { font-size: clamp(2.1rem, 4.1vw, 3.3rem); line-height: 1.1; letter-spacing: -0.02em; }
  h2 { font-size: clamp(1.9rem, 3.4vw, 2.6rem); line-height: 1.1; }
  h3 { font-size: 1.28rem; line-height: 1.25; letter-spacing: -0.005em; }
  p { margin: 0; }
  a { color: var(--brand-ink); text-decoration: none; }
  a:hover { text-decoration: underline; text-underline-offset: 3px; }

  .eyebrow { font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.16em; text-transform: uppercase; color: var(--brand-ink); font-weight: 500; }
  .lead { font-size: 1.22rem; line-height: 1.5; color: var(--body); }
  .kicker { color: var(--muted); }

  header.nav { position: sticky; top: 0; z-index: 50; background: color-mix(in srgb, var(--bg) 82%, transparent); backdrop-filter: saturate(1.2) blur(12px); border-bottom: 1px solid transparent; transition: border-color .3s ease; }
  header.nav.scrolled { border-bottom-color: var(--line); }
  .nav-inner { display: flex; align-items: center; gap: 20px; height: 66px; }
  .brand { display: flex; align-items: center; gap: 10px; font-family: var(--font-serif); font-size: 1.32rem; color: var(--ink); font-weight: 700; letter-spacing: -0.01em; }
  .brand svg { width: 30px; height: 30px; display: block; }
  .nav-spacer { flex: 1; }
  .nav-links { display: flex; gap: 26px; align-items: center; }
  .nav-links a { color: var(--body); font-size: 0.95rem; font-weight: 500; }
  .nav-links a:hover { color: var(--ink); text-decoration: none; }
  @media (max-width: 720px) { .nav-links { display: none; } }

  .btn { display: inline-flex; align-items: center; gap: 9px; font-family: var(--font-sans); font-size: 0.98rem; font-weight: 600; padding: 12px 20px; border-radius: 11px; cursor: pointer; border: 1px solid transparent; transition: transform .12s ease, background .2s ease, box-shadow .2s ease, border-color .2s ease; line-height: 1; }
  .btn:hover { text-decoration: none; transform: translateY(-1px); }
  .btn:active { transform: translateY(0); }
  .btn-primary { background: var(--brand); color: #04150B; box-shadow: 0 1px 0 rgba(255,255,255,.25) inset, 0 10px 24px -12px color-mix(in srgb, var(--brand) 70%, transparent); }
  .btn-primary:hover { background: var(--brand-press); }
  .btn-ghost { background: var(--surface); color: var(--ink); border-color: var(--line-strong); box-shadow: var(--shadow-sm); }
  .btn-ghost:hover { border-color: var(--muted); }
  .btn svg { width: 18px; height: 18px; }
  .btn-sm { padding: 9px 15px; font-size: 0.9rem; border-radius: 9px; }
  :focus-visible { outline: 2.5px solid var(--brand); outline-offset: 3px; border-radius: 4px; }

  section { padding: 82px 0; border-top: 1px solid var(--line); }
  .sec-green { background: var(--bg); }
  .sec-white { background: var(--surface); }
  .sec-head { max-width: 640px; margin-bottom: 44px; }
  .sec-head h2 { margin-top: 12px; }
  .sec-head p { margin-top: 16px; font-size: 1.1rem; }

  .hero { border-top: none; padding-top: 66px; padding-bottom: 74px; }
  .hero h1 { margin-top: 18px; max-width: 880px; }
  .hero .lead { margin-top: 22px; max-width: 620px; }
  .hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; align-items: center; }
  .hero-note { font-family: var(--font-mono); font-size: 0.78rem; color: var(--muted); margin-top: 16px; display: flex; flex-wrap: wrap; gap: 6px 14px; }
  .hero-note b { color: var(--brand-ink); font-weight: 600; }
  .trustrow { display: flex; flex-wrap: wrap; gap: 8px 10px; margin-top: 26px; }
  .chip { display: inline-flex; align-items: center; gap: 7px; font-size: 0.86rem; color: var(--body); font-weight: 500; background: var(--surface); border: 1px solid var(--line); border-radius: 999px; padding: 7px 13px 7px 11px; box-shadow: var(--shadow-sm); }
  .chip .tick { color: var(--brand); display: inline-flex; }
  .chip svg { width: 15px; height: 15px; }

  .window { border-radius: 14px; overflow: hidden; border: 1px solid var(--line-strong); background: var(--surface); box-shadow: var(--shadow); }
  .window-bar { display: flex; align-items: center; gap: 8px; padding: 11px 14px; background: var(--surface-2); border-bottom: 1px solid var(--line); }
  .window-bar .dot { width: 11px; height: 11px; border-radius: 50%; background: var(--line-strong); }
  .window-bar .addr { margin-left: 10px; font-family: var(--font-mono); font-size: 0.74rem; color: var(--muted); background: var(--bg); border: 1px solid var(--line); border-radius: 6px; padding: 4px 10px; }

  .carousel { position: relative; }
  .car-viewport { overflow: hidden; }
  .car-track { display: flex; transition: transform .55s cubic-bezier(.4,0,.2,1); will-change: transform; }
  .car-slide { min-width: 100%; }
  .car-slide img { display: block; width: 100%; height: auto; }
  .car-btn { position: absolute; top: 50%; transform: translateY(-50%); width: 46px; height: 46px; border-radius: 50%; background: #2FB957; border: 1px solid #2FB957; color: #04150B; display: grid; place-items: center; cursor: pointer; box-shadow: 0 8px 22px -8px rgba(47,185,87,0.6); z-index: 3; transition: background .2s, transform .15s; }
  .car-btn:hover { background: #28A44E; border-color: #28A44E; transform: translateY(-50%) scale(1.06); }
  .car-prev { left: 16px; } .car-next { right: 16px; }
  .car-btn svg { width: 20px; height: 20px; }
  .car-cap { text-align: center; margin-top: 20px; font-family: var(--font-mono); font-size: 0.8rem; color: var(--muted); }
  .car-hint { text-align: center; margin-top: 8px; font-family: var(--font-mono); font-size: 0.72rem; letter-spacing: 0.04em; color: var(--muted); }
  .car-hint .cha { color: #2FB957; font-weight: 700; }
  .dots { display: flex; gap: 8px; justify-content: center; margin-top: 16px; }
  .dot-btn { width: 8px; height: 8px; border-radius: 50%; border: none; background: var(--line-strong); cursor: pointer; padding: 0; transition: background .25s, width .25s; }
  .dot-btn.active { background: var(--brand); width: 24px; border-radius: 5px; }
  .images-head { margin-bottom: 40px; max-width: 640px; }

  .why-grid { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 54px; align-items: start; }
  @media (max-width: 840px) { .why-grid { grid-template-columns: 1fr; gap: 34px; } }
  .grind { display: flex; flex-direction: column; gap: 2px; border-left: 2px solid var(--line-strong); padding-left: 22px; }
  .grind-item { padding: 13px 0; border-bottom: 1px dashed var(--line); }
  .grind-item:last-child { border-bottom: none; }
  .grind-item b { color: var(--ink); font-weight: 600; font-family: var(--font-serif); }
  .maths { margin-top: 26px; font-family: var(--font-mono); font-size: 0.92rem; color: var(--body); background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 18px 20px; box-shadow: var(--shadow-sm); }
  .maths .strike { color: var(--muted); text-decoration: line-through; }
  .maths .win { color: var(--brand-ink); font-weight: 700; }

  .steps { display: flex; flex-direction: column; gap: 26px; }
  .step { display: grid; grid-template-columns: 62px 1fr; gap: 22px; align-items: start; padding: 26px; border: 1px solid var(--line); border-radius: 16px; background: var(--surface-2); box-shadow: var(--shadow-sm); }
  .step-n { font-family: var(--font-mono); font-size: 0.82rem; font-weight: 600; color: var(--brand-ink); background: var(--brand-wash); border: 1px solid color-mix(in srgb, var(--brand) 22%, transparent); width: 46px; height: 46px; border-radius: 12px; display: grid; place-items: center; }
  .step h3 { margin-bottom: 8px; }
  .step p { font-size: 1.02rem; }

  .guard { display: flex; align-items: flex-start; gap: 16px; background: var(--brand-wash); border: 1px solid color-mix(in srgb, var(--brand) 30%, transparent); border-radius: 14px; padding: 20px 22px; margin-bottom: 40px; }
  .guard .seal { flex: none; width: 40px; height: 40px; border-radius: 11px; background: var(--brand); color: #04150B; display: grid; place-items: center; }
  .guard .seal svg { width: 22px; height: 22px; }
  .guard-t { font-family: var(--font-serif); font-weight: 700; color: var(--ink); font-size: 1.1rem; }
  .guard-s { color: var(--brand-ink); font-weight: 500; font-size: 0.98rem; margin-top: 2px; }
  .promises { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
  @media (max-width: 720px) { .promises { grid-template-columns: 1fr; } }
  .promise { display: grid; grid-template-columns: 26px 1fr; gap: 12px; padding: 18px 20px; border: 1px solid var(--line); border-radius: 13px; background: var(--surface); }
  .promise .x { color: var(--brand); margin-top: 3px; }
  .promise .x svg { width: 20px; height: 20px; }
  .promise b { display: block; color: var(--ink); font-family: var(--font-serif); font-weight: 600; font-size: 1.04rem; margin-bottom: 3px; }
  .promise span.d { font-size: 0.95rem; color: var(--body); }

  .feat { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: 16px; overflow: hidden; }
  @media (max-width: 840px) { .feat { grid-template-columns: 1fr 1fr; } }
  @media (max-width: 560px) { .feat { grid-template-columns: 1fr; } }
  .feat-cell { background: var(--surface-2); padding: 24px 22px; }
  .feat-cell .lbl { font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); }
  .feat-cell h3 { font-size: 1.08rem; margin: 10px 0 6px; }
  .feat-cell p { font-size: 0.96rem; }

  .install-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
  @media (max-width: 720px) { .install-grid { grid-template-columns: 1fr; } }
  .os-card { border: 1px solid var(--line); border-radius: 16px; background: var(--surface-2); padding: 26px; box-shadow: var(--shadow-sm); display: flex; flex-direction: column; gap: 16px; }
  .os-head { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; }
  .os-top { display: flex; align-items: center; gap: 12px; }
  .os-card .os-ico { width: 34px; height: 34px; color: var(--ink); }
  .os-card h3 { font-size: 1.15rem; }
  .os-card .file { font-family: var(--font-mono); font-size: 0.78rem; color: var(--muted); }
  .os-card .firstrun { font-size: 0.9rem; color: var(--body); background: var(--surface); border: 1px solid var(--line); border-radius: 10px; padding: 12px 14px; }
  .os-card .firstrun b { color: var(--ink); }
  .req { margin-top: 26px; font-size: 0.98rem; color: var(--body); display: flex; flex-wrap: wrap; gap: 10px 22px; }
  .req .r { display: inline-flex; align-items: center; gap: 8px; }
  .req .r .tick { color: var(--brand); display: inline-flex; }
  .req svg { width: 16px; height: 16px; }

  .faq-grid { display: grid; grid-template-columns: 0.82fr 1.18fr; gap: 56px; align-items: start; }
  @media (max-width: 820px) { .faq-grid { grid-template-columns: 1fr; gap: 26px; } }
  .faq-head { margin-bottom: 0; }
  .faq { display: flex; flex-direction: column; }
  details { border-bottom: 1px solid var(--line); padding: 4px 0; }
  details summary { cursor: pointer; list-style: none; padding: 20px 40px 20px 0; position: relative; font-family: var(--font-serif); font-weight: 600; color: var(--ink); font-size: 1.14rem; }
  details summary::-webkit-details-marker { display: none; }
  details summary::after { content: "+"; position: absolute; right: 6px; top: 50%; transform: translateY(-50%); font-family: var(--font-mono); font-size: 1.5rem; color: var(--brand-ink); line-height: 1; }
  details[open] summary::after { content: "\2013"; }
  details .a { padding: 0 40px 22px 0; color: var(--body); font-size: 1.02rem; }

  .cta-band { text-align: center; }
  .cta-band h2 { margin-bottom: 8px; }
  .cta-band .lead { margin: 0 auto 28px; max-width: 720px; }
  .cta-band .hero-cta { justify-content: center; }
  .cta-band .eyebrow { display: block; }

  footer { background: #0B1611; color: #AEC0B5; padding: 66px 0 40px; border-top: 1px solid #1E2C24; }
  .foot-top { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 34px; }
  @media (max-width: 820px) { .foot-top { grid-template-columns: 1fr 1fr; gap: 34px 28px; } }
  .foot-brand2 { display: flex; align-items: center; gap: 10px; font-family: var(--font-serif); font-weight: 700; color: #F0F5F1; font-size: 1.25rem; }
  .foot-brand2 svg { width: 28px; height: 28px; }
  .foot-tag { margin-top: 16px; font-size: 0.92rem; color: #8DA093; max-width: 290px; line-height: 1.55; }
  .foot-col h4 { font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.14em; text-transform: uppercase; color: #6C8074; font-weight: 500; margin: 0 0 16px; }
  .foot-col ul { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 12px; }
  .foot-col a { color: #C3D2C8; font-size: 0.95rem; }
  .foot-col a:hover { color: #fff; text-decoration: none; }
  .foot-bottom { display: flex; flex-wrap: wrap; gap: 10px 18px; justify-content: space-between; align-items: center; margin-top: 50px; padding-top: 24px; border-top: 1px solid #1E2C24; font-size: 0.85rem; color: #7C8F84; }
  .foot-bottom .fam { font-family: var(--font-mono); letter-spacing: 0.02em; }
  .foot-bottom b { color: #C3D2C8; font-weight: 600; }

  .reveal { opacity: 0; transform: translateY(14px); transition: opacity .7s cubic-bezier(.2,.7,.2,1), transform .7s cubic-bezier(.2,.7,.2,1); }
  .reveal.in { opacity: 1; transform: none; }
  @media (prefers-reduced-motion: reduce) {
    .reveal { opacity: 1; transform: none; transition: none; }
    .btn, .btn:hover, .car-btn:hover { transition: none; transform: none; }
    .car-track { transition: none; }
  }