:root{
  --bg:#f4f7fb; --card:#fff; --line:rgba(20,40,70,.12); --text:#0d1622;
  --muted:#5b6a7d; --accent:#1e8fff; --accent2:#66c2ff; --shadow:0 12px 32px rgba(30,143,255,.18);
}
@media (prefers-color-scheme: dark){
  :root{ --bg:#070b12; --card:#0e1520; --line:rgba(120,180,255,.14); --text:#eaf1fb;
         --muted:#8595aa; --shadow:0 12px 32px rgba(30,143,255,.28); }
}
*{margin:0;padding:0;box-sizing:border-box}
body{background:var(--bg);color:var(--text);
  font-family:-apple-system,BlinkMacSystemFont,"SF Pro Display","Segoe UI",Roboto,sans-serif;
  line-height:1.6;padding:0 24px 60px;
  background-image:radial-gradient(900px 480px at 50% -220px, rgba(30,143,255,.12), transparent 70%)}
.wrap{max-width:760px;margin:0 auto}
header{display:flex;align-items:center;gap:12px;padding:26px 0 40px}
.mark{width:38px;height:38px;border-radius:12px;display:flex;align-items:center;justify-content:center;
  background:linear-gradient(135deg,var(--accent2),var(--accent));color:#fff;font-weight:800;font-size:17px}
.brand{font-weight:700;letter-spacing:-.02em;font-size:17px}
nav{margin-left:auto;display:flex;gap:18px;font-size:14px}
nav a{color:var(--muted);text-decoration:none}
nav a:hover{color:var(--text)}
h1{font-size:clamp(30px,6vw,46px);line-height:1.12;letter-spacing:-.03em;font-weight:800;margin-bottom:16px}
h2{font-size:20px;letter-spacing:-.02em;margin:34px 0 10px}
p{color:var(--muted);font-size:16px;margin-bottom:14px}
.lead{font-size:18px;max-width:560px;margin-bottom:28px}
.cta{display:inline-flex;align-items:center;gap:10px;padding:15px 26px;border-radius:14px;
  background:linear-gradient(135deg,var(--accent2),var(--accent));color:#fff;text-decoration:none;
  font-weight:600;box-shadow:var(--shadow)}
.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:14px;margin:38px 0}
.tile{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:18px}
.tile b{display:block;margin-bottom:6px;font-size:15px}
.tile span{color:var(--muted);font-size:14px}
article{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:26px}
article li{color:var(--muted);font-size:15px;margin:0 0 8px 18px}
footer{color:var(--muted);font-size:13px;padding-top:40px;opacity:.75}
footer a{color:var(--muted)}
.center{text-align:center;padding-top:60px}
.big{font-size:64px;font-weight:800;letter-spacing:-.04em;margin-bottom:10px}