:root {
  --bg: #f6f7f9;
  --card: #ffffff;
  --text: #15181d;
  --muted: #5b6370;
  --line: #e3e6eb;
  --brand: #1f6feb;
  --brand-dark: #1557c0;
  --tg: #229ed9;
  --ok: #1a7f37;
  --warn: #b7791f;
  --bad: #c62828;
  --radius: 14px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1216;
    --card: #171b21;
    --text: #e8ebef;
    --muted: #9aa3ae;
    --line: #262c35;
    --brand: #4c8dff;
    --brand-dark: #3a78e6;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
main, header, footer { max-width: 760px; margin: 0 auto; padding: 0 16px; }
a { color: var(--brand); }
h1 { font-size: clamp(28px, 6vw, 40px); line-height: 1.15; margin: 0 0 14px; letter-spacing: -0.01em; }
h2 { font-size: 24px; line-height: 1.25; margin: 0 0 14px; }
h3 { font-size: 18px; margin: 0 0 6px; }
p { margin: 0 0 12px; }
.muted { color: var(--muted); }
.small { font-size: 14px; }

.top { display: flex; align-items: center; justify-content: space-between; padding-top: 18px; }
.logo { font-weight: 800; font-size: 20px; text-decoration: none; color: var(--text); }
.logo span { color: var(--brand); }

.hero { padding: 40px 0 28px; }
.lead { font-size: 19px; color: var(--muted); }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 52px; padding: 14px 22px; border-radius: 12px;
  background: var(--tg); color: #fff; font-weight: 700; text-decoration: none;
  border: 0; cursor: pointer; font-size: 17px;
}
.btn:hover { filter: brightness(0.95); }
.btn.secondary { background: transparent; color: var(--brand); border: 2px solid var(--brand); }
.btn-row { display: flex; flex-wrap: wrap; gap: 12px; margin: 18px 0 8px; }

section { padding: 28px 0; border-top: 1px solid var(--line); }
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 18px; }
.steps { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }
.step-n {
  display: inline-grid; place-items: center; width: 30px; height: 30px; border-radius: 50%;
  background: var(--brand); color: #fff; font-weight: 700; margin-bottom: 8px;
}

/* demo: a bot message as it looks in Telegram */
.chat { display: grid; gap: 10px; max-width: 460px; }
.bubble { border-radius: 16px; padding: 12px 14px; font-size: 15.5px; line-height: 1.5; }
.bubble.bot { background: var(--card); border: 1px solid var(--line); border-top-left-radius: 4px; }
.bubble.me { background: #dcf3d0; color: #15181d; justify-self: end; border-top-right-radius: 4px; }
.voice { display: flex; align-items: center; gap: 10px; }
.voice .wave { flex: 1; height: 18px; background: repeating-linear-gradient(90deg, currentColor 0 2px, transparent 2px 5px); opacity: .35; border-radius: 4px; }
.voice .play { width: 32px; height: 32px; border-radius: 50%; background: var(--tg); flex: none; }
.chips { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 4px; }
.chip { font-size: 13.5px; border: 1px solid var(--line); border-radius: 8px; padding: 6px 9px; background: var(--card); }

.price { font-size: 32px; font-weight: 800; }
ul.ticks { padding: 0; margin: 0 0 12px; list-style: none; }
ul.ticks li { padding-left: 26px; position: relative; margin: 6px 0; }
ul.ticks li::before { content: "✓"; position: absolute; left: 0; color: var(--ok); font-weight: 800; }

details { border: 1px solid var(--line); border-radius: 12px; background: var(--card); padding: 12px 14px; margin: 8px 0; }
summary { cursor: pointer; font-weight: 600; }
details p { margin: 10px 0 0; color: var(--muted); }

footer { padding: 28px 16px 40px; border-top: 1px solid var(--line); color: var(--muted); font-size: 14px; }
footer nav { display: flex; flex-wrap: wrap; gap: 14px; margin-bottom: 10px; }

/* legal pages */
.doc { padding: 28px 0 10px; }
.doc h2 { font-size: 20px; margin-top: 26px; }
.doc li { margin: 4px 0; }