:root{
  --bg:#0b0d16; --panel:#12141f; --panel2:#181b29; --line:#262a3d;
  --ink:#e8ecf6; --muted:#97a0b8; --indigo:#6366f1; --cyan:#22d3ee; --green:#34d399;
  --mono:"SFMono-Regular",Consolas,"Liberation Mono",Menlo,monospace;
  --radius:12px;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:"Hiragino Sans","Yu Gothic UI","Noto Sans JP",system-ui,sans-serif;background:var(--bg);color:var(--ink);line-height:1.8;font-size:16px}
.wrap{max-width:1140px;margin:0 auto;padding:0 22px}
a{color:var(--cyan);text-decoration:none}
a:hover{text-decoration:underline}
header.site{position:sticky;top:0;z-index:50;background:rgba(11,13,22,.9);backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
.top{display:flex;align-items:center;gap:14px;height:64px}
.logo{display:flex;align-items:center;gap:9px;color:var(--ink)}
.logo-i{width:34px;height:34px;border-radius:9px;background:linear-gradient(135deg,var(--indigo),var(--cyan));display:grid;place-items:center;font-weight:900;color:#fff;font-size:18px}
.logo .word{font-weight:800;font-size:20px;letter-spacing:.3px}
.nav-toggle{display:none;background:none;border:1px solid var(--line);color:var(--ink);font-size:20px;width:42px;height:42px;border-radius:8px;cursor:pointer}
nav.main{display:flex;align-items:center;gap:2px;margin-left:auto;flex-wrap:wrap}
nav.main a{color:var(--muted);padding:8px 10px;border-radius:8px;font-size:14px;font-weight:600}
nav.main a:hover{color:var(--ink);background:var(--panel);text-decoration:none}
nav.main a.active{color:#fff;background:rgba(99,102,241,.18);border:1px solid rgba(99,102,241,.4)}
.btn{display:inline-block;background:linear-gradient(120deg,var(--indigo),var(--cyan));color:#fff;padding:12px 22px;border-radius:9px;font-weight:700;transition:transform .12s}
.btn:hover{text-decoration:none;transform:translateY(-2px)}
.btn.sm{background:linear-gradient(120deg,var(--indigo),var(--cyan));color:#fff;padding:7px 14px;font-size:13px}
.btn.ghost{background:transparent;border:1px solid var(--line);color:var(--ink)}
/* hero */
.hero{padding:70px 0 54px;background:radial-gradient(900px 360px at 10% -10%,rgba(99,102,241,.2),transparent 60%),radial-gradient(700px 300px at 95% 10%,rgba(34,211,238,.12),transparent 60%)}
.hero .split{display:grid;grid-template-columns:.8fr 1.2fr;gap:40px;align-items:center}
.eyebrow{color:var(--green);font-family:var(--mono);font-size:13px;letter-spacing:.05em;margin-bottom:14px}
.hero h1{font-size:48px;line-height:1.15;font-weight:900;letter-spacing:-.5px;margin-bottom:18px}
.hero .sub{color:var(--muted);font-size:16.5px;max-width:60ch;margin-bottom:24px}
.cta-row{display:flex;gap:12px;flex-wrap:wrap;margin-bottom:24px}
.chips{display:flex;flex-wrap:wrap;gap:9px}
.chips span{background:var(--panel);border:1px solid var(--line);color:var(--ink);font-family:var(--mono);font-size:12.5px;padding:6px 12px;border-radius:7px}
.code-card{background:#0f111d;border:1px solid var(--line);border-radius:14px;padding:18px;font-family:var(--mono);box-shadow:0 20px 50px rgba(0,0,0,.4)}
.cc-bar{display:flex;gap:6px;margin-bottom:14px}
.cc-bar span{width:11px;height:11px;border-radius:50%;background:var(--line)}
.cc-bar span:first-child{background:#f87171}.cc-bar span:nth-child(2){background:#fbbf24}.cc-bar span:last-child{background:#34d399}
.code-card pre{color:var(--green);font-size:14px;line-height:1.9;white-space:pre-wrap}
/* blk */
.blk{padding:50px 0}
.blk.alt{background:var(--panel)}
h2.sec{font-size:26px;font-weight:800;margin-bottom:8px}
p.sec-sub{color:var(--muted);margin-bottom:26px}
.grid{display:grid;gap:16px}
.g4{grid-template-columns:repeat(4,1fr)}
.g3{grid-template-columns:repeat(3,1fr)}
.g2{grid-template-columns:repeat(2,1fr)}
.card{background:var(--bg);border:1px solid var(--line);border-radius:var(--radius);padding:22px}
.blk.alt .card{background:var(--panel2)}
.card h3{font-size:17px;margin-bottom:8px;color:#fff}
.card p{color:var(--muted);font-size:14.5px}
.scard{background:var(--bg);border:1px solid var(--line);border-radius:var(--radius);padding:20px}
.blk.alt .scard{background:var(--panel2)}
.scard .n{font-family:var(--mono);color:var(--green);font-size:13px}
.scard h3{font-size:16.5px;margin:6px 0 8px;color:#fff}
.scard p{color:var(--muted);font-size:14px}
.note-p{color:var(--muted);font-size:14px;margin-top:18px;border-left:3px solid var(--indigo);padding-left:12px}
/* stats */
.stat-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.stat-grid div{background:var(--panel2);border:1px solid var(--line);border-radius:var(--radius);padding:18px;text-align:center}
.stat-grid b{display:block;font-size:26px;font-family:var(--mono);color:var(--cyan);font-weight:800}
.stat-grid span{color:var(--muted);font-size:13px}
/* pagehead */
.pagehead{padding:52px 0 28px;background:radial-gradient(700px 240px at 10% 0%,rgba(99,102,241,.16),transparent 60%)}
.pagehead h1{font-size:34px;font-weight:900;margin:8px 0 10px}
.pagehead .sub{color:var(--muted);max-width:70ch}
.crumb{color:var(--muted);font-size:13px}
/* steps / qa */
.steps{display:grid;gap:16px}
.step{display:flex;gap:18px;background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:20px}
.step .n{flex:none;width:38px;height:38px;border-radius:50%;background:linear-gradient(135deg,var(--indigo),var(--cyan));color:#fff;display:grid;place-items:center;font-weight:800;font-family:var(--mono)}
.step h3{font-size:16.5px;margin-bottom:4px}
.step p{color:var(--muted);font-size:14.5px}
.qa{background:var(--panel);border:1px solid var(--line);border-radius:var(--radius);padding:20px 22px;margin-bottom:14px}
.qa h3{font-size:16.5px;margin-bottom:6px}
.qa p{color:var(--muted);font-size:14.5px}
footer.site{border-top:1px solid var(--line);padding:30px 0 40px;background:#080a10}
.foot-brand{font-weight:700;margin-bottom:8px}
.foot-links{color:var(--muted);font-size:13.5px;margin-bottom:8px}
.foot-links a{color:var(--muted)}
.foot-note{color:#6d7590;font-size:13px;max-width:72ch}
.foot-copy{color:#4f586f;font-size:12.5px;margin-top:8px}
@media(max-width:960px){
  .g4{grid-template-columns:repeat(2,1fr)}
  .g3{grid-template-columns:repeat(2,1fr)}
  .hero .split{grid-template-columns:1fr}
  .code-card{order:-1}
  .nav-toggle{display:block;margin-left:auto}
  nav.main{position:fixed;top:64px;right:0;width:min(78%,300px);height:calc(100vh - 64px);background:var(--panel);flex-direction:column;align-items:flex-start;padding:16px;gap:4px;display:none;border-left:1px solid var(--line)}
  nav.main.open{display:flex}
  nav.main a{width:100%}
}
@media(max-width:560px){
  .g4,.g3,.g2{grid-template-columns:1fr}
  .stat-grid{grid-template-columns:1fr 1fr}
  .hero h1{font-size:34px}
  .pagehead h1{font-size:26px}
}