:root{--ink:#10212b;--muted:#5d6b74;--base:#f5f7f4;--card:#fff;--main:#5b21b6;--accent:#ec4899;--line:#dbe3df}*{box-sizing:border-box}body{margin:0;color:var(--ink);background:var(--base);font-family:system-ui,-apple-system,"Noto Sans JP",sans-serif;line-height:1.8}a{color:inherit}header,footer,main{max-width:1160px;margin:auto}header{display:flex;align-items:center;justify-content:space-between;padding:20px 24px}nav{display:flex;gap:18px;flex-wrap:wrap}.brand{text-decoration:none;font-weight:800}.mark{display:inline-grid;place-items:center;background:var(--main);color:white;border-radius:8px;padding:5px 8px;margin-right:9px}.hero{margin:12px 24px 36px;padding:clamp(34px,7vw,80px);border-radius:28px;color:white;background:linear-gradient(135deg,var(--main),#0b1620);position:relative;overflow:hidden}.hero:after{content:"";position:absolute;width:280px;height:280px;border:60px solid var(--accent);border-radius:50%;opacity:.17;right:-80px;top:-120px}.eyebrow{font-weight:800;letter-spacing:.12em;text-transform:uppercase;color:var(--accent)}h1{font-size:clamp(2.1rem,6vw,4.8rem);line-height:1.08;margin:.25em 0}.hero p{max-width:700px;font-size:1.1rem}.button{display:inline-block;text-decoration:none;background:var(--accent);color:#142018;font-weight:800;padding:12px 20px;border-radius:999px;margin:8px 8px 0 0}.button.alt{background:white}.section{margin:34px 24px;padding:30px;background:var(--card);border:1px solid var(--line);border-radius:22px}.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.card{padding:20px;border:1px solid var(--line);border-radius:16px;text-decoration:none;background:white}.card:hover{transform:translateY(-2px);box-shadow:0 12px 25px #0001}.card span{color:var(--main);font-weight:800}.calc{display:grid;grid-template-columns:1fr 1fr;gap:18px}.panel{padding:20px;border-radius:16px;background:#f7faf9;border:1px solid var(--line)}label{display:grid;grid-template-columns:1fr 140px;gap:8px;margin:10px 0}input,select{width:100%;padding:10px;border:1px solid #b8c6c0;border-radius:8px;font:inherit}.result{font-size:1.5rem;font-weight:800;color:var(--main);padding-top:12px}.table{overflow:auto}table{width:100%;border-collapse:collapse}th,td{padding:12px;border-bottom:1px solid var(--line);text-align:left}th{background:#eef3f1}.formula{padding:16px;border-left:5px solid var(--accent);background:#f7faf9}.note{color:var(--muted);font-size:.92rem}.breadcrumbs{margin:10px 24px;color:var(--muted)}article.prose{max-width:880px;margin:30px auto;padding:32px;background:white;border:1px solid var(--line);border-radius:22px}article.prose h2{margin-top:2em;color:var(--main)}.checklist li{margin:.5em 0}footer{padding:40px 24px;color:var(--muted)}footer nav{margin:10px 0}@media(max-width:760px){header{align-items:flex-start;gap:12px;flex-direction:column}.grid,.calc{grid-template-columns:1fr}.section{padding:20px;margin:20px 12px}.hero{margin:8px 12px;padding:32px 22px}label{grid-template-columns:1fr}article.prose{margin:20px 12px;padding:22px}}
/* Revenue path */
.affiliate-offer{margin:34px 24px;padding:28px;background:var(--card,#fff);border:1px solid var(--line,#d8dee8);border-radius:20px}.affiliate-offer h2{margin:.25em 0}.affiliate-label{display:inline-block;margin:0 0 6px;padding:3px 9px;border-radius:999px;background:#eef2f6;color:#46515b;font-size:.78rem;font-weight:800}.affiliate-links,.affiliate-banner{margin:18px 0}.affiliate-banner img{max-width:100%;height:auto}.affiliate-note{font-size:.9rem;color:var(--muted,#667085)}article.prose .affiliate-offer{margin:32px 0}@media(max-width:760px){.affiliate-offer{margin:22px 12px;padding:22px}}