/* AI Fellow design system (fellaiw.com): dark ground, Inter 400/500, blue-to-purple gradient, mint accent. Dark theme only. */
:root {
  --brand-blue: #185FA5;
  --brand-purple: #534AB7;
  --brand-teal: #1D9E75;
  --brand-mint: #5DCAA5;
  --brand-deep: #0C447C;
  --brand-gradient: linear-gradient(135deg, var(--brand-blue), var(--brand-purple));
  --bg: #111111;
  --surface: #1a1a1a;
  --surface-2: #222222;
  --line: #2a2a2a;
  --fg: #f0f0ee;
  --muted: #999999;
  --on-brand: #ffffff;
  --glow: rgba(83, 74, 183, 0.35);
  --shadow: 0 30px 80px rgba(0,0,0,0.55);
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color-scheme: dark;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-body); font-size: 16px; line-height: 1.6;
  background: var(--bg); color: var(--fg); -webkit-font-smoothing: antialiased;
}
a { color: var(--brand-mint); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3 { font-weight: 500; letter-spacing: -0.02em; line-height: 1.15; text-wrap: balance; }
h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); }
h2 { font-size: clamp(1.7rem, 3.4vw, 2.5rem); }
h3 { font-size: 1.15rem; }
p { color: var(--muted); }
.wrap {
  max-width: 1120px; margin: 0 auto;
  padding-left: max(16px, env(safe-area-inset-left, 0px));
  padding-right: max(16px, env(safe-area-inset-right, 0px));
}
section { padding-block: 5.5rem; }
.eyebrow { font-size: 0.75rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--brand-mint); margin-bottom: 1rem; display: block; }
.divider { width: 40px; height: 2px; background: var(--brand-gradient); margin: 1.25rem 0 1.5rem; }
.lead { font-size: 1.1rem; max-width: 60ch; }
.section-head { max-width: 42rem; margin-bottom: 3rem; }
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }
.section-head.center .divider { margin-left: auto; margin-right: auto; }
:focus-visible { outline: 2px solid var(--brand-mint); outline-offset: 3px; }

/* Buttons */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem;
  padding: 0.8rem 1.4rem; border-radius: 8px; /* app radius scale (docs/DESIGN-SYSTEM.md section 3): no pills */ font-weight: 500; font-size: 0.95rem;
  border: 1px solid transparent; cursor: pointer; font-family: inherit; white-space: nowrap;
  transition: transform .15s ease, box-shadow .15s ease, background .15s ease;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary { background: var(--brand-gradient); color: var(--on-brand); box-shadow: 0 10px 30px var(--glow); }
.btn-primary:hover { box-shadow: 0 14px 36px var(--glow); }
.btn-ghost { border-color: var(--line); color: var(--fg); background: transparent; }
.btn-ghost:hover { border-color: var(--muted); }
.btn-sm { padding: 0.55rem 1rem; font-size: 0.85rem; }
.btn svg { width: 16px; height: 16px; stroke: currentColor; fill: none; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }

/* Nav */
.nav { position: sticky; top: 0; z-index: 9; background: rgba(17, 17, 17, 0.88); backdrop-filter: blur(14px); border-bottom: 1px solid var(--line); }
.nav .wrap { display: flex; align-items: center; gap: 1.5rem; height: 68px; }
.brand { display: flex; align-items: center; gap: 0.7rem; color: var(--fg); }
.brand:hover { text-decoration: none; }
.brand svg { width: 36px; height: 36px; flex-shrink: 0; }
.brand .name { font-size: 1.25rem; font-weight: 500; letter-spacing: -0.03em; line-height: 1; }
.brand .by { display: block; font-size: 0.6rem; letter-spacing: 0.25em; color: var(--muted); margin-top: 0.25rem; }
.nav-links { display: flex; gap: 1.5rem; margin-left: auto; font-size: 0.9rem; }
.nav-links a { color: var(--muted); }
.nav-links a:hover { color: var(--fg); text-decoration: none; }
.nav-cta { display: flex; gap: 0.6rem; align-items: center; }
@media (max-width: 820px) { .nav-links { display: none; } .nav-cta { margin-left: auto; } .nav-cta .btn-ghost { display: none; } }

/* Hero */
.hero { padding-block: 4.5rem 5rem; position: relative; overflow: hidden; }
.hero::after { content: ""; position: absolute; width: 700px; height: 700px; right: -200px; top: -200px; border-radius: 50%; background: radial-gradient(closest-side, var(--glow), transparent); pointer-events: none; }
.hero .wrap { display: grid; grid-template-columns: 7fr 5fr; gap: 3rem; align-items: center; position: relative; z-index: 1; }
.hero h1 { margin-bottom: 1rem; }
.hero .lead { margin-bottom: 2rem; }
.price-line { display: flex; flex-wrap: wrap; align-items: baseline; gap: 0.6rem 1rem; margin-bottom: 0.6rem; }
.price-line .amount { font-size: 2.2rem; font-weight: 500; letter-spacing: -0.03em; font-variant-numeric: tabular-nums; }
.price-line .per { color: var(--muted); font-size: 0.95rem; }
.fine { font-size: 0.85rem; color: var(--muted); max-width: 52ch; }
.hero-ctas { display: flex; flex-wrap: wrap; gap: 0.8rem; margin: 1.6rem 0 1rem; }
.currency { display: inline-flex; border: 1px solid var(--line); border-radius: 8px; overflow: hidden; vertical-align: middle; }
.currency button { background: none; border: 0; font-family: inherit; font-size: 0.78rem; letter-spacing: 0.08em; color: var(--muted); padding: 0.3rem 0.85rem; cursor: pointer; }
.currency button.active { background: var(--surface-2); color: var(--fg); }
.currency button:hover:not(.active) { color: var(--brand-mint); }
.os { display: inline-flex; align-items: center; gap: 0.45rem; }
.os svg { width: 14px; height: 14px; fill: currentColor; }

/* Mock app window */
.app { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; box-shadow: var(--shadow); overflow: hidden; max-width: 100%; aspect-ratio: 4 / 3.1; display: flex; flex-direction: column; font-size: 0.7rem; }
.app-bar { display: flex; align-items: center; gap: 0.5rem; padding: 0.55rem 0.8rem; border-bottom: 1px solid var(--line); background: var(--surface-2); }
.app-bar .dot { width: 9px; height: 9px; border-radius: 50%; background: var(--line); }
.app-bar .title { margin-left: 0.5rem; color: var(--muted); }
.app-tools { display: flex; gap: 0.4rem; padding: 0.5rem 0.8rem; border-bottom: 1px solid var(--line); overflow: hidden; }
.app-tools span { padding: 0.2rem 0.55rem; border-radius: 6px; background: var(--surface-2); color: var(--muted); white-space: nowrap; }
.app-tools span.on { background: var(--brand-gradient); color: var(--on-brand); }
.app-body { flex: 1; display: grid; grid-template-columns: 56px 1fr; min-height: 0; }
.app-side { border-right: 1px solid var(--line); padding: 0.6rem 0.5rem; display: flex; flex-direction: column; gap: 0.45rem; }
.app-side i { display: block; height: 40px; border-radius: 4px; background: var(--surface-2); border: 1px solid var(--line); }
.app-side i.on { border-color: var(--brand-mint); }
.app-canvas { background: var(--bg); padding: 1rem; display: flex; justify-content: center; align-items: flex-start; overflow: hidden; }
.page { width: 78%; aspect-ratio: 1 / 1.3; background: #fff; color: #222; border-radius: 3px; box-shadow: 0 10px 30px rgba(0,0,0,0.35); padding: 9% 9% 0; position: relative; overflow: hidden; }
.page .ln { height: 5px; border-radius: 3px; background: #d9d9d5; margin-bottom: 6px; }
.page .ln.h { height: 9px; width: 60%; background: #2a2a2a; margin-bottom: 12px; }
.page .ln.w70 { width: 70%; } .page .ln.w85 { width: 85%; } .page .ln.w50 { width: 50%; }
.page .hl { background: rgba(93, 202, 165, 0.45); }
.page .redact { background: #111; height: 5px; width: 40%; border-radius: 2px; margin-bottom: 6px; }
.page .sig { position: absolute; right: 9%; bottom: 10%; width: 44%; border: 1px dashed var(--brand-blue); border-radius: 4px; padding: 6px 8px; color: var(--brand-blue); font-size: 0.6rem; line-height: 1.3; }
.page .sig b { display: block; font-weight: 500; font-family: 'Segoe Script', 'Brush Script MT', cursive; font-size: 0.95rem; color: var(--brand-purple); }
.page .img { width: 40%; aspect-ratio: 16/10; border-radius: 3px; background: linear-gradient(135deg, #185FA5, #5DCAA5); margin: 8px 0 10px; }
.note { position: absolute; left: 4%; top: 32%; background: #fff8c5; color: #5a4a00; padding: 4px 6px; border-radius: 3px; font-size: 0.55rem; box-shadow: 0 3px 8px rgba(0,0,0,0.25); transform: rotate(-2deg); }
.app-status { border-top: 1px solid var(--line); padding: 0.4rem 0.8rem; display: flex; gap: 1rem; color: var(--muted); }
.app-status .ok { color: var(--brand-mint); }
@media (max-width: 900px) { .hero .wrap { grid-template-columns: 1fr; } .app { max-width: 520px; } }

/* Feature cards */
.cards { display: grid; gap: 1.25rem; }
.cards-4 { grid-template-columns: repeat(4, 1fr); }
.cards-3 { grid-template-columns: repeat(3, 1fr); }
@media (max-width: 1000px) { .cards-4 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 760px) { .cards-4, .cards-3 { grid-template-columns: 1fr; } }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: 16px; padding: 1.6rem; display: flex; flex-direction: column; gap: 0.75rem; min-width: 0; }
.card .icon { width: 44px; height: 44px; border-radius: 12px; background: var(--brand-gradient); display: grid; place-items: center; color: var(--on-brand); margin-bottom: 0.4rem; }
.card .icon svg { width: 22px; height: 22px; stroke: currentColor; fill: none; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.card p { font-size: 0.95rem; flex: 1; }
.band { background: var(--surface); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.band .card { background: var(--bg); }

/* Pricing */
.plan-grid { display: grid; grid-template-columns: 1.1fr 1fr; gap: 2rem; align-items: stretch; }
@media (max-width: 860px) { .plan-grid { grid-template-columns: 1fr; } }
.plan { position: relative; border-radius: 20px; padding: 2px; background: var(--brand-gradient); box-shadow: 0 30px 70px var(--glow); }
.plan-inner { background: var(--surface); border-radius: 18px; padding: 2.2rem; height: 100%; display: flex; flex-direction: column; gap: 1.2rem; }
.plan .badge { position: absolute; top: -0.8rem; left: 2rem; background: var(--brand-gradient); color: var(--on-brand); font-size: 0.7rem; letter-spacing: 0.14em; text-transform: uppercase; padding: 0.35rem 0.8rem; border-radius: 6px; }
.plan-head { display: flex; justify-content: space-between; align-items: flex-start; gap: 1rem; flex-wrap: wrap; }
.plan-head h3 { font-size: 1.5rem; }
.plan-price { display: flex; align-items: baseline; gap: 0.5rem; flex-wrap: wrap; }
.plan-price .amount { font-size: 3.2rem; font-weight: 500; letter-spacing: -0.04em; line-height: 1; font-variant-numeric: tabular-nums; }
.plan-price .per { color: var(--muted); }
.plan ul { list-style: none; display: grid; gap: 0.55rem; font-size: 0.95rem; }
.plan li { display: flex; gap: 0.6rem; align-items: flex-start; }
.plan li::before { content: ""; flex-shrink: 0; width: 18px; height: 18px; margin-top: 3px; border-radius: 50%; background: var(--brand-mint); -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M20 6 9 17l-5-5'/%3E%3C/svg%3E") center/70% no-repeat; mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M20 6 9 17l-5-5'/%3E%3C/svg%3E") center/70% no-repeat; }
.plan .btn { align-self: stretch; }
.trial-box { border: 1px solid var(--line); border-radius: 20px; padding: 2.2rem; background: var(--surface); display: flex; flex-direction: column; gap: 1rem; }
.trial-box h3 { font-size: 1.5rem; }
.timeline { list-style: none; display: grid; gap: 0.9rem; margin-top: 0.5rem; }
.timeline li { display: grid; grid-template-columns: 72px 1fr; gap: 1rem; font-size: 0.95rem; }
.timeline .day { font-size: 0.72rem; letter-spacing: 0.14em; text-transform: uppercase; color: var(--brand-mint); padding-top: 0.25rem; }
.timeline li strong { font-weight: 500; display: block; color: var(--fg); }
.timeline li span { color: var(--muted); }
.dl-group { margin-top: auto; display: flex; flex-direction: column; gap: 0.6rem; }
.dl-group .btn { align-self: flex-start; }
.dl-group .alt { font-size: 0.85rem; color: var(--muted); }
.sysreq { margin-top: 2rem; display: flex; flex-wrap: wrap; gap: 0.6rem 1.6rem; justify-content: center; font-size: 0.85rem; color: var(--muted); }
.sysreq span::before { content: ""; display: inline-block; width: 6px; height: 6px; border-radius: 50%; background: var(--brand-mint); margin-right: 0.55rem; vertical-align: middle; }

/* Benefits */
.benefits { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem 2.5rem; }
@media (max-width: 860px) { .benefits { grid-template-columns: 1fr 1fr; } }
@media (max-width: 560px) { .benefits { grid-template-columns: 1fr; } }
.benefit { display: grid; grid-template-columns: 28px 1fr; gap: 0.9rem; min-width: 0; }
.benefit .mark { width: 28px; height: 2px; background: var(--brand-gradient); margin-top: 0.8rem; }
.benefit h3 { font-size: 1.05rem; margin-bottom: 0.3rem; }
.benefit p { font-size: 0.92rem; }

/* Engine numbers */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.25rem; }
@media (max-width: 860px) { .stats { grid-template-columns: 1fr 1fr; } }
.stat { border-left: 2px solid var(--brand-purple); padding-left: 1.2rem; min-width: 0; }
.stat .n { font-size: 2.4rem; font-weight: 500; letter-spacing: -0.03em; line-height: 1.1; font-variant-numeric: tabular-nums; }
.stat .l { color: var(--muted); font-size: 0.9rem; margin-top: 0.3rem; }
.formats { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-top: 2.5rem; }
.formats span { font-size: 0.78rem; letter-spacing: 0.06em; padding: 0.35rem 0.75rem; border: 1px solid var(--line); border-radius: 6px; color: var(--muted); }

/* FAQ */
.faq { max-width: 760px; margin: 0 auto; }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary { list-style: none; cursor: pointer; padding: 1.2rem 2.4rem 1.2rem 0; font-weight: 500; position: relative; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; position: absolute; right: 0.3rem; top: 1.05rem; font-size: 1.4rem; font-weight: 400; color: var(--brand-mint); transition: transform .2s ease; }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq details p { padding-bottom: 1.3rem; font-size: 0.95rem; max-width: 65ch; }
.faq details p + p { margin-top: -0.6rem; }

/* Footer CTA */
.final { padding-block: 5rem; }
.final .wrap { display: grid; grid-template-columns: 1fr auto; gap: 2rem; align-items: center; background: var(--surface); border: 1px solid var(--line); border-radius: 24px; padding: 2.5rem; }
@media (max-width: 760px) { .final .wrap { grid-template-columns: 1fr; } }
.final h2 { margin-bottom: 0.4rem; }
.final .ctas { display: flex; flex-wrap: wrap; gap: 0.8rem; }
footer { border-top: 1px solid var(--line); padding-block: 2rem calc(1rem + env(safe-area-inset-bottom, 0px)); font-size: 0.85rem; color: var(--muted); }
footer .wrap { display: flex; flex-wrap: wrap; gap: 1rem 2rem; justify-content: space-between; align-items: center; }
footer .links { display: flex; flex-wrap: wrap; gap: 1.2rem; align-items: center; }
footer .links a { color: var(--muted); }
footer .email { color: var(--fg); user-select: all; }

/* Sticky promo */
.sticky { position: fixed; left: 0; right: 0; bottom: 0; z-index: 8; background: rgba(26, 26, 26, 0.92); backdrop-filter: blur(14px); border-top: 1px solid var(--line); transform: translateY(110%); transition: transform .3s ease; padding-bottom: env(safe-area-inset-bottom, 0px); }
.sticky.show { transform: translateY(0); }
.sticky .wrap { display: flex; align-items: center; gap: 1rem; padding-block: 0.7rem; }
.sticky .text { flex: 1; min-width: 0; font-size: 0.9rem; }
.sticky .text strong { font-weight: 500; }
.sticky .text span { color: var(--muted); }
.sticky .close { background: none; border: 0; color: var(--muted); font-size: 1.3rem; cursor: pointer; line-height: 1; padding: 0.3rem; }
@media (max-width: 560px) { .sticky .text span { display: none; } }

@media (prefers-reduced-motion: reduce) { * { transition: none !important; } html { scroll-behavior: auto; } }