:root {
    --bg: #0d1117;
    --card: #161b22;
    --text: #e6edf3;
    --muted: #8b949e;
    --accent: #3fb950;
    --danger: #f85149;
    --border: #30363d;
    /* White on #3fb950 is only 2.54:1 (fails WCAG 4.5) — buttons use
       a darker green (5.08:1); inputs get a visible 3:1 border. */
    --accent-btn: #1a7f37;
    --accent-btn-dark: #15682e;
    --border-strong: #6e7681;
    color-scheme: dark;
  }
  * { margin: 0; padding: 0; box-sizing: border-box; }
  body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
  }
  .container { max-width: 680px; margin: 0 auto; padding: 0 20px; }
  header { padding: 20px 0; text-align: center; }
  .logo { font-size: 1.4rem; font-weight: 700; }
  .logo span { color: var(--accent); }
  .hero { text-align: center; padding: 48px 0 32px; }
  .hero h1 { font-size: 2.1rem; line-height: 1.25; margin-bottom: 16px; }
  .hero h1 em { font-style: normal; color: var(--danger); }
  .hero p.sub { color: var(--muted); font-size: 1.1rem; max-width: 520px; margin: 0 auto; }
  .demo {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 28px;
    margin: 32px 0;
    text-align: center;
  }
  .demo .label { font-size: .8rem; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); margin-bottom: 14px; }
  .words { display: flex; justify-content: center; gap: 12px; flex-wrap: wrap; }
  .word {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 12px 20px;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--accent);
    min-width: 110px;
  }
  .timer { margin-top: 14px; color: var(--muted); font-size: .85rem; }
  .timer b { color: var(--text); }
  .phone-pair { display: flex; justify-content: center; gap: 24px; margin-top: 18px; color: var(--muted); font-size: .85rem; }
  .match { color: var(--accent); font-weight: 700; }
  h2 { font-size: 1.5rem; margin: 40px 0 12px; text-align: center; }
  .steps { counter-reset: step; margin: 24px 0; }
  .step {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 18px 20px 18px 60px;
    margin-bottom: 12px;
    position: relative;
  }
  .step::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    left: 18px; top: 16px;
    width: 28px; height: 28px;
    background: var(--accent);
    color: var(--bg);
    border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    font-weight: 700;
  }
  .step b { display: block; margin-bottom: 2px; }
  .step span { color: var(--muted); font-size: .95rem; }
  .stats { display: flex; gap: 12px; flex-wrap: wrap; margin: 28px 0; }
  .stat {
    flex: 1; min-width: 150px;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 16px;
    text-align: center;
  }
  .stat .num { font-size: 1.6rem; font-weight: 700; color: var(--danger); }
  .stat .desc { font-size: .85rem; color: var(--muted); }
  .source { font-size: .75rem; color: var(--muted); text-align: center; margin-top: -12px; margin-bottom: 24px; }
  .cta {
    background: var(--card);
    border: 1px solid var(--accent);
    border-radius: 16px;
    padding: 32px 28px;
    margin: 40px 0;
    text-align: center;
  }
  .cta h2 { margin-top: 0; }
  .cta p { color: var(--muted); margin-bottom: 20px; }
  button:hover { background: var(--accent-btn-dark); }
  a:focus-visible, summary:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
  .faq { margin: 32px 0; }
  .faq details {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 14px 18px;
    margin-bottom: 10px;
  }
  .faq summary { font-weight: 600; cursor: pointer; }
  .faq p { color: var(--muted); margin-top: 10px; font-size: .95rem; }
  footer { text-align: center; padding: 32px 0 48px; color: var(--muted); font-size: .85rem; }
  footer a { color: var(--muted); }