:root{--accent:#1F5FFF;--navy:#0f1f3d;--slate:#33415c;--muted:#64748b;--line:#e2e8f0;--soft:#f6f8fb}
  *{box-sizing:border-box;margin:0;padding:0}
  body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;color:var(--slate);line-height:1.7;font-size:17px;background:#fff;-webkit-font-smoothing:antialiased}
  a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}
  .wrap{max-width:820px;margin:0 auto;padding:0 22px}
  header{border-bottom:1px solid var(--line);position:sticky;top:0;background:rgba(255,255,255,.95);backdrop-filter:blur(10px);z-index:10}
  .nav{display:flex;align-items:center;justify-content:space-between;height:64px;max-width:1120px;margin:0 auto;padding:0 22px}
  .brand{display:flex;align-items:center;gap:10px;font-weight:800;color:var(--navy);font-size:19px}
  .brand .mark{display:inline-flex;width:30px;height:30px;border-radius:8px;background:linear-gradient(135deg,var(--accent),var(--navy));align-items:center;justify-content:center;color:#fff;font-weight:800;font-size:14px}
  .nav a.back{font-size:14px;font-weight:600;color:var(--muted)}
  main{padding:48px 0 60px}
  h1{color:var(--navy);font-size:34px;margin-bottom:8px;letter-spacing:-.01em}
  .sub{color:var(--muted);font-size:15px;margin-bottom:34px}
  h2{color:var(--navy);font-size:21px;margin:34px 0 8px}
  h3{color:var(--navy);font-size:17px;margin:20px 0 6px}
  p{margin-bottom:12px}
  ul{margin:0 0 12px 22px}li{margin-bottom:6px}
  .ph{background:#fff7e6;border:1px solid #f0d699;color:#8a6400;border-radius:6px;padding:1px 6px;font-size:14px;font-weight:600}
  footer{border-top:1px solid var(--line);background:var(--soft);padding:28px 0;font-size:14px;color:var(--muted)}
  footer .wrap{display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px}
  footer a{color:var(--muted)}

  h2{color:var(--navy);font-size:20px;margin:30px 0 8px}
  .box{background:var(--soft);border:1px solid var(--line);border-radius:12px;padding:18px 22px;margin-bottom:8px}