:root {
  --bg: #F5F6FA;
  --surface: #FFFFFF;
  --text: #0E1224;
  --muted: #5B6178;
  --line: #E4E6EE;
  --brand: #2F5BFF;
  --brand-soft: #E8EDFF;
  --green: #1FA560;
  --red: #E5484D;
  --gold: #F2C14E;
  --radius: 22px;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0A0E1F;
    --surface: #141A30;
    --text: #F2F4FA;
    --muted: #9AA2BC;
    --line: #242B45;
    --brand: #6F8BFF;
    --brand-soft: #1C2547;
    --green: #3DD68C;
    --red: #FF6B70;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.55 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Inter", "Segoe UI", Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }
.wrap { max-width: 760px; margin: 0 auto; padding: 0 20px; }

/* Top bar */
.nav { position: sticky; top: 0; z-index: 10; backdrop-filter: saturate(180%) blur(18px); -webkit-backdrop-filter: saturate(180%) blur(18px); background: color-mix(in srgb, var(--bg) 78%, transparent); border-bottom: 1px solid var(--line); }
.nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 58px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; color: var(--text); font-size: 17px; }
.brand:hover { text-decoration: none; }
.brand img { width: 30px; height: 30px; border-radius: 8px; }
.nav-links { display: flex; gap: 20px; font-size: 15px; }
.nav-links a { color: var(--muted); }
.nav-links a[aria-current="page"] { color: var(--text); font-weight: 600; }

/* Document pages */
.doc { padding-top: 44px; padding-bottom: 72px; }
.doc h1 { font-size: clamp(32px, 6vw, 44px); line-height: 1.1; letter-spacing: -0.02em; margin: 0 0 8px; }
.doc .lead { color: var(--muted); margin: 0 0 32px; }
.doc h2 { font-size: 21px; letter-spacing: -0.01em; margin: 36px 0 8px; }
.doc p, .doc li { color: var(--text); }
.doc ul { padding-left: 22px; }
.doc li { margin: 6px 0; }
.card { background: var(--surface); border-radius: var(--radius); padding: 22px 24px; border: 1px solid var(--line); }
.card + .card { margin-top: 14px; }
.muted { color: var(--muted); }

/* FAQ */
details { background: var(--surface); border: 1px solid var(--line); border-radius: 16px; padding: 16px 20px; margin: 10px 0; }
details summary { cursor: pointer; font-weight: 600; list-style: none; display: flex; justify-content: space-between; gap: 12px; }
details summary::-webkit-details-marker { display: none; }
details summary::after { content: "+"; color: var(--muted); font-weight: 400; font-size: 22px; line-height: 1; }
details[open] summary::after { content: "–"; }
details p { margin: 10px 0 0; color: var(--muted); }

/* Buttons */
.btn { display: inline-flex; align-items: center; gap: 10px; background: var(--brand); color: #fff; font-weight: 600; padding: 14px 24px; border-radius: 999px; font-size: 17px; }
.btn:hover { text-decoration: none; filter: brightness(1.06); }
.btn.dark { background: var(--text); color: var(--bg); }
.btn svg { width: 20px; height: 20px; }

/* Landing */
.hero { text-align: center; padding-top: 64px; padding-bottom: 40px; }
.hero .app-icon { width: 112px; height: 112px; border-radius: 26px; box-shadow: 0 18px 40px -12px rgba(47, 91, 255, .55); }
.hero h1 { font-size: clamp(40px, 8vw, 64px); line-height: 1.04; letter-spacing: -0.03em; margin: 26px 0 14px; }
.hero h1 span { background: linear-gradient(120deg, #2F5BFF, #7B5CFF 60%, #2F5BFF); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero p { font-size: 20px; color: var(--muted); max-width: 560px; margin: 0 auto 30px; }
.hero small { display: block; margin-top: 14px; color: var(--muted); font-size: 14px; }

.demo { margin: 10px auto 0; max-width: 460px; background: var(--surface); border: 1px solid var(--line); border-radius: 26px; padding: 8px 18px; box-shadow: 0 30px 60px -30px rgba(14, 18, 36, .35); text-align: left; }
.row { display: flex; align-items: center; gap: 14px; padding: 14px 0; }
.row + .row { border-top: 1px solid var(--line); }
.thumb { width: 46px; height: 46px; border-radius: 12px; background: var(--brand-soft); display: grid; place-items: center; font-size: 22px; flex: none; }
.row .name { font-weight: 600; font-size: 15px; line-height: 1.3; }
.row .meta { font-size: 13px; color: var(--muted); }
.row .price { margin-left: auto; text-align: right; font-weight: 700; font-variant-numeric: tabular-nums; }
.down { color: var(--green); font-weight: 600; }
.up { color: var(--red); font-weight: 600; }

.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 14px; padding: 56px 0 24px; }
.feature { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; }
.feature .icon { width: 40px; height: 40px; border-radius: 11px; display: grid; place-items: center; font-size: 20px; margin-bottom: 14px; }
.feature h3 { margin: 0 0 6px; font-size: 17px; }
.feature p { margin: 0; color: var(--muted); font-size: 15px; }

.steps { padding: 32px 0; }
.steps h2, .pro h2 { text-align: center; font-size: clamp(28px, 5vw, 38px); letter-spacing: -0.02em; margin: 0 0 24px; }
.step { display: flex; gap: 16px; align-items: flex-start; }
.step + .step { margin-top: 18px; }
.step b { flex: none; width: 34px; height: 34px; border-radius: 50%; background: var(--brand); color: #fff; display: grid; place-items: center; font-size: 15px; }
.step p { margin: 4px 0 0; color: var(--muted); }

.pro { padding: 40px 0; }
.pro .card { background: linear-gradient(145deg, #121833, #0A0E1F); color: #F2F4FA; border: 0; padding: 30px; }
.pro .card h3 { margin: 0 0 14px; font-size: 22px; display: flex; align-items: center; gap: 10px; }
.pro .card h3 .crown { color: var(--gold); }
.pro ul { list-style: none; padding: 0; margin: 0; }
.pro li { padding: 8px 0; border-top: 1px solid rgba(255,255,255,.08); color: #D5DAEA; }
.pro li:first-child { border-top: 0; }
.pro li b { color: #fff; }

.cta { text-align: center; padding: 40px 0 72px; }

footer { border-top: 1px solid var(--line); padding: 28px 0 40px; font-size: 14px; color: var(--muted); }
footer .wrap { display: flex; flex-wrap: wrap; gap: 12px 22px; justify-content: space-between; }
footer nav { display: flex; gap: 18px; flex-wrap: wrap; }
footer a { color: var(--muted); }

@media (max-width: 520px) {
  .nav-links { gap: 14px; font-size: 14px; }
  .hero { padding-top: 44px; }
}