:root{--bg:#fff;--ink:#0f172a;--muted:#64748b;--brand:#2563eb;--brand-dark:#1d4ed8;--line:#e2e8f0;--soft:#f8fafc}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{color:var(--ink);background:var(--bg);margin:0;font-family:ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial,sans-serif;line-height:1.6}a{color:var(--brand);text-decoration:none}a:hover{text-decoration:underline}.container{width:min(1120px,92%);margin-inline:auto}.site-header{border-bottom:1px solid var(--line);background:var(--bg);z-index:20;position:sticky;top:0}.site-header .inner{justify-content:space-between;align-items:center;gap:24px;padding-block:14px;display:flex}.brand{color:var(--ink);font-size:1.05rem;font-weight:800}.brand:hover{text-decoration:none}.nav{flex-wrap:wrap;gap:18px;font-size:.95rem;display:flex}.nav a{color:var(--muted)}.nav a:hover{color:var(--ink);text-decoration:none}.hero{padding-block:72px 48px}.hero h1{letter-spacing:-.02em;margin:0 0 16px;font-size:clamp(2rem,5vw,3.2rem);line-height:1.08}.hero p{color:var(--muted);max-width:44rem;font-size:1.15rem}.hero .cta{flex-wrap:wrap;gap:12px;margin-top:28px;display:flex}.btn{background:var(--brand);color:#fff;border-radius:10px;justify-content:center;align-items:center;padding:12px 20px;font-weight:600;display:inline-flex}.btn:hover{background:var(--brand-dark);text-decoration:none}.btn.ghost{color:var(--brand);border:1px solid var(--line);background:0 0}.features{grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:18px;margin-block:24px;display:grid}.card{border:1px solid var(--line);background:var(--soft);border-radius:14px;padding:22px}.card h3{margin:0 0 8px}.card p{color:var(--muted);margin:0;font-size:.95rem}.section{padding-block:40px}.section h2{margin:0 0 16px;font-size:1.6rem}.tool-card{border:1px solid var(--line);background:#fff;border-radius:14px;padding:20px}.tool-card h3{margin:0 0 6px}.section-label{color:var(--brand);text-transform:uppercase;letter-spacing:.08em;font-size:.8rem;font-weight:700}.lead{color:var(--muted)}.rule{border-top:1px solid var(--line);margin-block:32px 0}.site-footer{border-top:1px solid var(--line);color:var(--muted);margin-top:64px;padding-block:32px;font-size:.9rem}.site-footer .container{flex-wrap:wrap;justify-content:space-between;gap:16px;display:flex}label{margin-bottom:6px;font-size:.85rem;font-weight:600;display:block}input,select{border:1px solid var(--line);width:100%;font:inherit;color:var(--ink);background:#fff;border-radius:10px;padding:10px 12px}input:focus,select:focus{outline:2px solid var(--brand);outline-offset:1px;border-color:var(--brand)}.form-grid{grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:18px;display:grid}.result-box{border:1px solid var(--line);background:#fafbff;border-radius:14px;padding:20px}.result-box strong{font-variant-numeric:tabular-nums}table{border-collapse:collapse;width:100%;font-size:.92rem}th,td{text-align:left;border-bottom:1px solid var(--line);padding:10px 12px}th{color:var(--muted);font-size:.82rem;font-weight:600}code{background:var(--soft);border-radius:6px;padding:2px 6px;font-size:.9em}ul.tight{margin:.4rem 0;padding-left:1.2rem}ul.tight li{margin-bottom:.4rem}.disclaimer{color:var(--muted);border-top:1px dashed var(--line);margin-top:32px;padding-top:16px;font-size:.8rem}.two-col{grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:24px;display:grid}@media (max-width:640px){.hero{padding-block:48px 32px}.nav{gap:12px}}