:root{--bg:#ffffff;--card:#fafafa;--ink:#111111;--mute:#666666;--line:#e6e6e6;--accent:#111111}*{box-sizing:border-box}body,html{margin:0;background:var(--bg);color:var(--ink)}body{font-family:var(--font-sans),var(--font-jp),"Hiragino Sans",sans-serif;font-size:16px;line-height:1.6}a{color:inherit}button,input,select,textarea{font:inherit;color:inherit}img,video{max-width:100%;display:block}.nav{position:-webkit-sticky;position:sticky;top:0;z-index:10;display:flex;align-items:center;gap:20px;padding:16px 28px;background:var(--bg);border-bottom:1px solid var(--line)}.nav-mark{font-weight:600;text-decoration:none;letter-spacing:.02em}.nav nav{display:flex;gap:20px;margin-left:auto;font-size:14px}.nav nav a{color:var(--mute);text-decoration:none}.nav nav a:hover{color:var(--ink)}.wrap{max-width:880px;margin:0 auto;padding:48px 24px 80px}.hero{padding:24px 0 40px}.hero h1{font-size:clamp(28px,5vw,44px);font-weight:500;letter-spacing:-.03em;line-height:1.25;margin:0 0 16px}.lede{color:var(--mute);margin:0 0 20px;max-width:38em}.row{display:flex;gap:10px;flex-wrap:wrap}.btn{display:inline-flex;align-items:center;justify-content:center;padding:10px 18px;text-decoration:none;border:1px solid var(--ink);background:var(--ink);color:#fff;font-size:14px}.btn.ghost{background:transparent;color:var(--ink)}.section{margin:56px 0}.section h2{font-size:13px;font-weight:600;letter-spacing:.12em;color:var(--mute);margin:0 0 18px}.demo-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));grid-gap:12px;gap:12px}.card{background:var(--card);border:1px solid var(--line);padding:20px;text-decoration:none;display:flex;flex-direction:column;gap:8px;min-height:160px}.card:hover{border-color:var(--ink)}.card h3{margin:0;font-size:18px;font-weight:500}.card p{margin:0;font-size:14px;flex:1 1}.card p,.meta{color:var(--mute)}.meta{font-size:13px}.offer-grid{display:grid;grid-gap:0;gap:0}.offer{border-top:1px solid var(--line);padding:18px 0}.offer:last-child{border-bottom:1px solid var(--line)}.offer b{display:block;font-size:16px;font-weight:500;margin-bottom:4px}.offer p{margin:0;color:var(--mute);font-size:14px}.form{display:grid;grid-gap:14px;gap:14px}.form label{display:grid;grid-gap:6px;gap:6px;font-size:14px;font-weight:600}.form input,.form select,.form textarea{width:100%;padding:10px 12px;border:1px solid var(--line);background:#fff;border-radius:0}.form input:focus,.form select:focus,.form textarea:focus{outline:none;border-color:var(--ink)}.note{font-size:13px;color:var(--mute);font-weight:400}.ok{background:#f4f4f4;border:1px solid var(--line)}.err,.ok{padding:12px 14px}.err{background:#fff5f5;border:1px solid #cc4444}.demo-bar{display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;align-items:center;background:#fafafa;border-bottom:1px solid var(--line);padding:10px 0;margin-bottom:24px;font-size:13px;color:var(--mute)}.demo-bar a{color:var(--ink)}.foot{max-width:880px;margin:0 auto;padding:24px;color:var(--mute);font-size:13px;border-top:1px solid var(--line)}.invoice{background:#fff;color:#111;border:1px solid #111;padding:28px}.invoice h2{margin:0 0 4px;letter-spacing:.3em;text-align:center}.invoice table{width:100%;border-collapse:collapse;margin-top:16px}.invoice td,.invoice th{border-bottom:1px solid #ddd;padding:8px 4px;text-align:left}.invoice .sum{text-align:right;font-size:20px;margin-top:16px}.ans-item,.youken-item{padding:10px 12px;display:grid;grid-gap:4px;gap:4px}.ans-item,.links-card,.youken-item{background:#fff;border:1px solid var(--line)}.links-card{padding:28px 20px;max-width:420px;margin:0 auto;text-align:center}.links-card a.link{display:block;border:1px solid var(--ink);padding:12px;margin:8px 0;text-decoration:none;font-weight:600}.prompt{background:#111;color:#eee;padding:14px;font-family:var(--font-mono),ui-monospace,monospace;font-size:13px;white-space:pre-wrap;line-height:1.5}@media print{.demo-bar,.foot,.nav,.no-print{display:none!important}body{background:#fff}}