:root{--paper: #fbfbf7;--grid: rgba(23, 35, 59, .055);--ink: #17233b;--ink-soft: #4a5570;--line: #dfe2d9;--blue: #2450d8;--blue-soft: #eef1fc;--red: #d9382c;--card: #ffffff;--radius: 10px;--mono: ui-monospace, "SF Mono", "Cascadia Mono", Menlo, Consolas, monospace;--sans: system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif}*{box-sizing:border-box}html{scroll-behavior:smooth}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation:none!important;transition:none!important}}body{margin:0;font-family:var(--sans);font-size:16px;line-height:1.6;color:var(--ink);background-color:var(--paper);background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px);background-size:24px 24px}a{color:var(--blue);text-underline-offset:3px}a:hover{color:var(--red)}:focus-visible{outline:3px solid var(--blue);outline-offset:2px;border-radius:4px}.skip-link{position:absolute;left:-9999px;background:var(--ink);color:#fff;padding:8px 16px;z-index:100}.skip-link:focus{left:8px;top:8px}.container{max-width:1080px;margin:0 auto;padding:0 20px}.site-header{border-bottom:2px solid var(--ink);background:var(--paper)}.site-header .container{display:flex;align-items:center;justify-content:space-between;min-height:64px;gap:16px;flex-wrap:wrap}.logo{font-weight:800;font-size:22px;letter-spacing:-.02em;color:var(--ink);text-decoration:none}.logo em{font-style:normal;color:var(--red)}.site-nav{display:flex;gap:18px;flex-wrap:wrap}.site-nav a{color:var(--ink-soft);text-decoration:none;font-size:15px;padding:6px 2px}.site-nav a:hover{color:var(--red)}.site-footer{border-top:2px solid var(--ink);margin-top:72px;padding:28px 0 40px;font-size:14px;color:var(--ink-soft)}.site-footer .container{display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap}.site-footer a{color:var(--ink-soft)}.hero{padding:56px 0 32px}.hero h1{font-size:clamp(30px,5vw,46px);line-height:1.12;letter-spacing:-.03em;margin:0 0 12px;max-width:640px}.hero h1 mark{background:none;color:var(--red)}.hero p{font-size:18px;color:var(--ink-soft);max-width:560px;margin:0}.category-label{font-family:var(--mono);font-size:17px;font-weight:700;text-transform:uppercase;letter-spacing:.14em;color:var(--red);margin:44px 0 14px;padding-bottom:6px;border-bottom:2px solid var(--red);display:inline-block}.tool-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:14px;padding:0;margin:0;list-style:none}.tool-card{display:block;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:18px 18px 16px;text-decoration:none;color:var(--ink);min-height:44px;transition:border-color .15s ease,transform .15s ease}.tool-card:hover{border-color:var(--ink);transform:translateY(-2px);color:var(--ink)}.tool-card .tool-icon{color:var(--ink-soft);margin-bottom:10px;display:block;transition:color .15s ease}.tool-card:hover .tool-icon{color:var(--red)}.tool-card h2,.tool-card h3{font-size:17px;margin:0 0 6px;letter-spacing:-.01em}.tool-card p{font-size:14px;color:var(--ink-soft);margin:0}.breadcrumbs{font-size:13px;color:var(--ink-soft);margin:24px 0 8px}.breadcrumbs ol{list-style:none;display:flex;gap:6px;padding:0;margin:0;flex-wrap:wrap}.breadcrumbs li+li:before{content:"›";margin-right:6px;color:var(--line)}.breadcrumbs a{color:var(--ink-soft)}.tool-page h1{font-size:clamp(26px,4vw,38px);letter-spacing:-.025em;margin:8px 0}.tool-lede{font-size:17px;color:var(--ink-soft);max-width:640px;margin:0 0 24px}.tool-panel{background:var(--card);border:1px solid var(--ink);border-radius:var(--radius);padding:24px;box-shadow:4px 4px #17233b1f;max-width:640px}.field{margin-bottom:16px}.field label{display:block;font-size:14px;font-weight:600;margin-bottom:6px}.field input,.field select{width:100%;font-size:16px;font-family:var(--mono);padding:10px 12px;border:1px solid var(--line);border-radius:6px;background:var(--paper);color:var(--ink);min-height:44px}.field input:focus,.field select:focus{border-color:var(--blue);outline:2px solid var(--blue-soft)}.field-row{display:flex;gap:12px;flex-wrap:wrap}.field-row .field{flex:1 1 140px}.btn{display:inline-block;font-size:16px;font-weight:700;font-family:var(--sans);padding:12px 22px;min-height:44px;background:var(--ink);color:#fff;border:none;border-radius:6px;cursor:pointer}.btn:hover{background:var(--blue)}.btn-ghost{background:transparent;color:var(--ink);border:1px solid var(--ink);margin-left:8px}.btn-ghost:hover{background:var(--blue-soft);color:var(--ink)}.result{margin-top:20px;padding:16px 18px 16px 22px;border-left:4px solid var(--red);background:var(--blue-soft);border-radius:0 var(--radius) var(--radius) 0}.result .result-label{font-family:var(--mono);font-size:12px;text-transform:uppercase;letter-spacing:.12em;color:var(--ink-soft);margin-bottom:4px}.result .result-value{font-family:var(--mono);font-variant-numeric:tabular-nums;font-size:clamp(24px,4vw,34px);font-weight:700;line-height:1.2;word-break:break-all}.result .result-sub{font-size:14px;color:var(--ink-soft);margin-top:6px}.tool-content{max-width:720px;margin-top:48px}.tool-content h2{font-size:24px;letter-spacing:-.02em;margin:36px 0 12px;padding-bottom:6px;border-bottom:1px solid var(--line)}.tool-content p,.tool-content li{color:#2a3550;font-size:16px}.tool-content code{font-family:var(--mono);background:var(--blue-soft);padding:2px 6px;border-radius:4px;font-size:14px}.formula{font-family:var(--mono);background:var(--card);border:1px dashed var(--ink-soft);border-radius:var(--radius);padding:14px 18px;font-size:15px;overflow-x:auto}.faq details{border:1px solid var(--line);border-radius:var(--radius);background:var(--card);margin-bottom:10px;padding:0 16px}.faq summary{cursor:pointer;font-weight:600;padding:14px 0;min-height:44px;list-style-position:inside}.faq details[open] summary{border-bottom:1px solid var(--line)}.faq details p{padding-bottom:14px}.related{margin-top:48px}.related h2{font-size:20px;margin-bottom:14px}.prose{max-width:720px;padding:32px 0}.prose h1{letter-spacing:-.02em}@media(max-width:767px){.tool-panel{padding:18px 14px}.btn-ghost{margin-left:0;margin-top:8px}}