:root{--ink:#0f1622;--muted:#5b6675;--brand:#3b6cf6;--brand2:#7a5cf0;--good:#12a06a;--line:rgba(15,22,34,.1);--bg:#f6f8fc}
*{box-sizing:border-box}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Hiragino Sans","Noto Sans JP",sans-serif;color:var(--ink);background:var(--bg);line-height:1.9;font-size:16px}
a{color:var(--brand)}
.wrap{max-width:760px;margin:0 auto;padding:0 20px}
header{position:sticky;top:0;background:rgba(255,255,255,.85);backdrop-filter:blur(14px);border-bottom:1px solid var(--line);z-index:10}
.nav{display:flex;align-items:center;gap:12px;padding:14px 20px;max-width:760px;margin:0 auto}
.logo{font-weight:800;font-size:19px;text-decoration:none;color:var(--ink)}
.logo b{background:linear-gradient(135deg,var(--brand),var(--brand2));-webkit-background-clip:text;background-clip:text;color:transparent}
.cta{margin-left:auto;background:linear-gradient(135deg,var(--brand),var(--brand2));color:#fff;text-decoration:none;padding:9px 16px;border-radius:12px;font-weight:800;font-size:13.5px}
.crumb{font-size:12.5px;color:var(--muted);padding:18px 0 0}
.crumb a{color:var(--muted)}
article{background:#fff;border:1px solid var(--line);border-radius:18px;padding:34px 32px;margin:16px 0 30px;box-shadow:0 6px 20px rgba(16,24,40,.05)}
article h1{font-size:29px;line-height:1.45;letter-spacing:-.4px;margin:0 0 10px}
.meta{font-size:12.5px;color:var(--muted);margin-bottom:24px;padding-bottom:18px;border-bottom:1px solid var(--line)}
article h2{font-size:21px;margin:38px 0 12px;padding-left:13px;border-left:4px solid var(--brand);line-height:1.5}
article h3{font-size:17px;margin:26px 0 8px}
article p{margin:0 0 16px}
article ul,article ol{margin:0 0 18px;padding-left:22px}
article li{margin-bottom:7px}
.lead{font-size:16.5px;color:var(--muted)}
.box{background:linear-gradient(135deg,rgba(59,108,246,.06),rgba(122,92,240,.06));border:1px solid rgba(59,108,246,.2);border-radius:14px;padding:16px 20px;margin:22px 0;font-size:14.5px}
.box b{color:#254fd0}
.warn{background:linear-gradient(180deg,rgba(255,248,225,.9),rgba(255,250,235,.7));border:1px solid #f0e2ad;color:#6b5000;border-radius:14px;padding:16px 20px;margin:22px 0;font-size:14.5px}
table{width:100%;border-collapse:collapse;font-size:14px;margin:18px 0}
th,td{padding:11px 10px;border-bottom:1px solid var(--line);text-align:left}
th{background:#f0f3fa;font-weight:800}
.promo{background:linear-gradient(135deg,var(--brand),var(--brand2));color:#fff;border-radius:18px;padding:26px 28px;margin:34px 0 0;text-align:center}
.promo h3{margin:0 0 8px;font-size:19px;color:#fff}
.promo p{color:rgba(255,255,255,.9);font-size:14.5px;margin:0 0 16px}
.promo a{display:inline-block;background:#fff;color:#254fd0;text-decoration:none;font-weight:800;padding:13px 26px;border-radius:12px}
.related{margin:0 0 40px}
.related h2{font-size:18px;margin:0 0 12px}
.related a{display:block;background:#fff;border:1px solid var(--line);border-radius:14px;padding:15px 18px;margin-bottom:10px;text-decoration:none;color:var(--ink);font-weight:700;font-size:14.5px}
.related a:hover{border-color:var(--brand)}
.related span{display:block;color:var(--muted);font-weight:500;font-size:12.5px;margin-top:3px}
footer{background:#0f1622;color:#aab3c0;padding:34px 0;font-size:13px;margin-top:20px}
footer a{color:#cdd5e0;text-decoration:none;margin-right:16px}
@media(max-width:640px){article{padding:24px 20px;border-radius:14px}article h1{font-size:23px}article h2{font-size:18.5px}}