:root{--ink: #23262d;--ink-soft: #5b616e;--muted: #676d7a;--paper: #f7f4ee;--card: #ffffff;--line: #e7e2d8;--line-soft: #efeae1;--brand: #b8443a;--brand-deep: #93332b;--brand-soft: #faf0ee;--gold: #b8934a;--good: #1f7a4d;--good-soft: #eef7f1;--warn: #a8660f;--warn-soft: #fdf5e8;--radius: 14px;--radius-sm: 10px;--shadow: 0 1px 2px rgb(35 38 45 / .04), 0 8px 24px -12px rgb(35 38 45 / .12);--shadow-hover: 0 2px 4px rgb(35 38 45 / .06), 0 16px 40px -16px rgb(35 38 45 / .18);--font: -apple-system, BlinkMacSystemFont, "PingFang SC", "HarmonyOS Sans SC", "MiSans", "Noto Sans SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;--mono: "SF Mono", "JetBrains Mono", "Cascadia Code", Consolas, monospace}*{box-sizing:border-box}[hidden]{display:none!important}html{-webkit-text-size-adjust:100%}body{margin:0;font-family:var(--font);font-size:16px;line-height:1.75;color:var(--ink);background:var(--paper);-webkit-font-smoothing:antialiased}.wrap{max-width:1060px;margin:0 auto;padding:0 20px}h1,h2,h3{line-height:1.35;letter-spacing:.01em}a{color:var(--brand);text-decoration:none}a:hover{text-decoration:underline}.num,td.num,dd{font-variant-numeric:tabular-nums}.skip-link{position:absolute;left:-999px}.skip-link:focus{left:8px;top:8px;z-index:99;background:var(--card);padding:8px 14px;border-radius:var(--radius-sm);box-shadow:var(--shadow)}.site-header{background:var(--card);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20;backdrop-filter:saturate(1.4)}.header-inner{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:10px 20px;padding-top:12px;padding-bottom:12px}.brand{display:inline-flex;align-items:center;gap:10px;color:var(--ink);font-weight:800}.brand:hover{text-decoration:none}.brand-mark{display:grid;place-items:center;width:34px;height:34px;border-radius:10px;background:var(--brand);color:#fff;font-size:17px;font-weight:800;box-shadow:inset 0 -2px #0000001f}.brand-name{font-size:1.08rem;letter-spacing:.02em}.site-header nav{display:flex;flex-wrap:wrap;gap:4px 6px}.site-header nav a{color:var(--ink-soft);font-size:.94rem;font-weight:600;padding:6px 12px;border-radius:999px}.site-header nav a:hover{color:var(--brand);background:var(--brand-soft);text-decoration:none}.hero{padding:64px 0 36px;text-align:center;background:radial-gradient(640px 240px at 50% -60px,rgb(184 68 58 / .09),transparent 70%),radial-gradient(420px 200px at 85% 10%,rgb(184 147 74 / .08),transparent 70%)}.hero-kicker{display:inline-block;font-size:.82rem;font-weight:700;letter-spacing:.14em;color:var(--brand);background:var(--card);border:1px solid var(--line);border-radius:999px;padding:5px 16px;margin:0 0 18px}.hero h1{font-size:clamp(2.1rem,5vw,3rem);margin:0 0 16px;font-weight:900;letter-spacing:.02em}.hero-lead{max-width:640px;margin:0 auto;color:var(--ink-soft);font-size:1.05rem}.hero-stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:10px;max-width:760px;margin:26px auto 0}.hero-stats div{background:#ffffffb8;border:1px solid var(--line);border-radius:var(--radius-sm);padding:12px 14px;text-align:left}.hero-stats dt{font-size:.9rem;font-weight:800;color:var(--brand)}.hero-stats dd{margin:2px 0 0;font-size:.82rem;color:var(--ink-soft)}.tool-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(420px,1fr));gap:16px;margin:12px 0 8px}.tool-card{display:flex;align-items:center;gap:14px;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:20px;box-shadow:var(--shadow);transition:transform .15s ease,box-shadow .15s ease,border-color .15s ease}.tool-card:hover{transform:translateY(-2px);box-shadow:var(--shadow-hover);border-color:#d9d2c5;text-decoration:none}.tool-mark{flex:none;display:grid;place-items:center;width:46px;height:46px;border-radius:12px;background:var(--brand-soft);color:var(--brand);font-size:1.25rem;font-weight:800;border:1px solid #f0dcd8}.tool-body{flex:1;min-width:0}.tool-body h2{margin:0 0 2px;font-size:1.06rem;color:var(--ink)}.tool-body p{margin:0;font-size:.9rem;color:var(--muted);line-height:1.6}.tool-arrow{flex:none;color:#c8c1b3;font-weight:700;transition:transform .15s ease}.tool-card:hover .tool-arrow{transform:translate(3px);color:var(--brand)}.trust{margin:40px 0 64px;background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:26px 28px;box-shadow:var(--shadow)}.trust h2{margin:0 0 12px;font-size:1.15rem}.trust ul{margin:0;padding:0;list-style:none;display:grid;gap:10px}.trust li{position:relative;padding-left:26px;color:var(--ink-soft);font-size:.97rem}.trust li:before{content:"✓";position:absolute;left:0;top:1px;display:grid;place-items:center;width:18px;height:18px;border-radius:6px;background:var(--good-soft);color:var(--good);font-size:.72rem;font-weight:800}.breadcrumbs{display:flex;gap:8px;align-items:center;font-size:.88rem;color:var(--muted);padding:22px 0 0}.breadcrumbs span[aria-hidden]{color:#c9c2b4}.page-title{margin:6px 0 18px;font-size:clamp(1.7rem,3.6vw,2.3rem);font-weight:900;letter-spacing:.02em}.intro{color:var(--ink-soft);max-width:760px;margin-bottom:26px}.intro p{margin:0}.calc{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:26px;margin-bottom:28px}.field-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:16px 18px}.field{display:flex;flex-direction:column;gap:6px;min-width:0}.field-wide{grid-column:1 / -1}.field-label,.field label{font-size:.92rem;font-weight:700;color:var(--ink)}.field input[type=text],.field input[type=date]{width:100%;font:inherit;font-variant-numeric:tabular-nums;color:var(--ink);background:#fcfbf8;border:1px solid var(--line);border-radius:var(--radius-sm);padding:10px 12px;transition:border-color .15s ease,box-shadow .15s ease,background .15s ease}.field input::placeholder{color:#b8b2a5}.field input:focus{outline:none;background:#fff;border-color:var(--brand);box-shadow:0 0 0 3px #b8443a24}.hint{font-size:.82rem;color:var(--muted);line-height:1.55}.hint.warn{color:var(--warn)}.segmented{display:inline-flex;background:#f1ede5;border-radius:999px;padding:4px;gap:4px;width:fit-content}.segmented button{font:inherit;font-weight:700;font-size:.94rem;border:none;background:transparent;color:var(--ink-soft);padding:8px 22px;border-radius:999px;cursor:pointer;transition:all .15s ease}.segmented button.active{background:var(--card);color:var(--brand);box-shadow:0 1px 3px #0000001f}.radio-row{display:flex;flex-wrap:wrap;gap:8px}.radio-row label{display:inline-flex;align-items:center;gap:7px;font-weight:600;font-size:.94rem;color:var(--ink-soft);background:#fcfbf8;border:1px solid var(--line);border-radius:999px;padding:8px 16px;cursor:pointer;transition:all .15s ease}.radio-row label:hover{border-color:#d9d2c5}.radio-row input{accent-color:var(--brand)}.radio-row label:has(input:checked){border-color:var(--brand);color:var(--brand);background:var(--brand-soft)}.chip-row{display:flex;flex-wrap:wrap;gap:8px}.chip{font:inherit;font-size:.86rem;font-weight:600;font-variant-numeric:tabular-nums;color:var(--ink-soft);background:#fcfbf8;border:1px dashed #cfc8ba;border-radius:999px;padding:6px 14px;cursor:pointer;transition:all .15s ease}.chip:hover{color:var(--brand);border-color:var(--brand);border-style:solid;background:var(--brand-soft)}.form-actions{margin:20px 0 0}button{font-family:inherit}#calc-reset{font-size:.9rem;font-weight:600;color:var(--ink-soft);background:#f6f2ea;border:1px solid var(--line);border-radius:999px;padding:9px 20px;cursor:pointer;transition:all .15s ease}#calc-reset:hover{color:var(--brand);border-color:var(--brand)}.calc-error{margin-top:16px;background:var(--warn-soft);border:1px solid #ecd9b8;border-radius:var(--radius-sm);padding:12px 16px;color:#7a4d0a;font-size:.92rem}.calc-error ul{margin:0;padding-left:18px}.calc-results{margin-top:24px}.result-hero{display:grid;grid-template-columns:minmax(260px,1fr) minmax(260px,1.2fr);gap:20px;align-items:stretch;background:linear-gradient(135deg,#b8443a,#93332b);border-radius:var(--radius);padding:26px 28px;color:#fff;box-shadow:0 12px 32px -16px #93332b80}@media(max-width:720px){.result-hero{grid-template-columns:1fr}}.result-hero-item{display:flex;flex-direction:column;gap:2px;justify-content:center}.result-hero-item .result-label{font-size:.9rem;opacity:.85;font-weight:600}.result-big{font-size:clamp(2rem,4.6vw,2.7rem);font-weight:900;letter-spacing:.01em;font-variant-numeric:tabular-nums;line-height:1.15}.result-hero-item .result-sub{font-size:.84rem;opacity:.78}.result-side{margin:0;display:grid;grid-template-columns:1fr 1fr;gap:12px 20px;align-content:center}.result-side div{border-left:2px solid rgb(255 255 255 / .28);padding-left:14px}.result-side dt{font-size:.82rem;opacity:.8;font-weight:600}.result-side dd{margin:2px 0 0;font-size:1.12rem;font-weight:800;font-variant-numeric:tabular-nums}.result-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:12px;margin-top:16px}.result{background:#fcfbf8;border:1px solid var(--line-soft);border-radius:var(--radius-sm);padding:14px 16px;display:flex;flex-direction:column;gap:2px}.result-label{font-size:.84rem;color:var(--muted);font-weight:600}.result-value{font-size:1.28rem;font-weight:800;color:var(--ink);font-variant-numeric:tabular-nums}.result-value.is-good{color:var(--good)}.result.result-key{background:var(--brand-soft);border-color:#f0dcd8}.result.result-key .result-value{color:var(--brand-deep)}.result-sub{font-size:.8rem;color:var(--muted)}.result-sub.warn{color:var(--warn)}.mode-cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:16px;margin-top:20px}.mode-card{background:#fcfbf8;border:1px solid var(--line);border-radius:var(--radius);padding:22px}.mode-card h3{margin:0 0 4px;font-size:1.05rem;color:var(--ink)}.mode-desc{margin:0 0 14px;font-size:.88rem;color:var(--muted)}.mode-card dl{margin:0;display:grid;gap:8px}.mode-card dl div{display:flex;justify-content:space-space;align-items:baseline;gap:10px}.mode-card dl div{display:flex;justify-content:space-between;border-bottom:1px dashed var(--line-soft);padding-bottom:7px}.mode-card dl div:last-child{border-bottom:none;padding-bottom:0}.mode-sub{font-size:.8rem;color:var(--brand);font-weight:600;padding-bottom:4px}.mode-card dt{font-size:.9rem;color:var(--ink-soft);font-weight:600}.mode-card dd{margin:0;font-weight:800;font-variant-numeric:tabular-nums;font-size:1.02rem}.mode-card dd.is-good{color:var(--good)}.conclusion,.paidoff-note{margin-top:16px;background:var(--good-soft);border:1px solid #cde7d6;color:#14532d;border-radius:var(--radius-sm);padding:13px 16px;font-size:.95rem;line-height:1.7}.paidoff-note{background:var(--brand-soft);border-color:#f0dcd8;color:var(--brand-deep)}.table-head{display:flex;align-items:center;justify-content:space-between;gap:12px;margin:26px 0 10px}.table-head h3{margin:0;font-size:1.05rem}.btn-ghost{font-size:.85rem;font-weight:600;color:var(--ink-soft);background:#f6f2ea;border:1px solid var(--line);border-radius:999px;padding:7px 16px;cursor:pointer;transition:all .15s ease}.btn-ghost:hover{color:var(--brand);border-color:var(--brand)}.table-wrap{overflow-x:auto;border:1px solid var(--line-soft);border-radius:var(--radius-sm);background:#fff}table{width:100%;border-collapse:collapse;font-size:.92rem}thead th{text-align:left;font-size:.82rem;color:var(--ink-soft);background:#f8f5ef;padding:10px 14px;border-bottom:1px solid var(--line);white-space:nowrap}tbody td{padding:9px 14px;border-bottom:1px solid var(--line-soft);white-space:nowrap;font-variant-numeric:tabular-nums}tbody tr:last-child td{border-bottom:none}tbody tr:hover td{background:#fdfcfa}td.num{text-align:right}.table-expand{display:block;width:100%;margin-top:10px;font:inherit;font-size:.88rem;font-weight:600;color:var(--ink-soft);background:#f6f2ea;border:1px solid var(--line);border-radius:999px;padding:9px 16px;cursor:pointer;transition:all .15s ease}.table-expand:hover{color:var(--brand);border-color:var(--brand);background:var(--brand-soft)}.table-note{margin:10px 2px 0;font-size:.84rem;color:var(--muted)}.explanation{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:30px 32px;margin-bottom:24px}.explanation h2{font-size:1.3rem;margin:34px 0 12px;padding-top:20px;border-top:1px solid var(--line-soft)}.explanation h2:first-child{margin-top:0;padding-top:0;border-top:none}.explanation h3{font-size:1.05rem;margin:24px 0 8px;color:var(--ink)}.explanation p{color:var(--ink-soft);margin:0 0 12px}.explanation ul{margin:0 0 12px;padding-left:0;list-style:none}.explanation ul li{position:relative;padding-left:24px;color:var(--ink-soft);margin-bottom:10px}.explanation ul li:before{content:"";position:absolute;left:4px;top:.62em;width:7px;height:7px;border-radius:2px;background:var(--brand)}.formula{background:#faf7f0;border:1px solid var(--line);border-left:3px solid var(--gold);border-radius:var(--radius-sm);padding:14px 18px;margin:14px 0;overflow-x:auto}.formula pre{margin:0;font-family:var(--mono);font-size:.88rem;line-height:1.8;color:#4a4638;white-space:pre-wrap}.example-table{width:100%;border-collapse:collapse;margin:14px 0 18px;font-size:.94rem;background:#fff;border:1px solid var(--line-soft);border-radius:var(--radius-sm);overflow:hidden}.example-table th{background:#f8f5ef;text-align:left;padding:10px 14px;border-bottom:1px solid var(--line);font-size:.86rem;color:var(--ink-soft)}.example-table td{padding:10px 14px;border-bottom:1px solid var(--line-soft);font-variant-numeric:tabular-nums}.example-table tr:last-child td{border-bottom:none}.faq{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:30px 32px;margin-bottom:24px}.faq h2{font-size:1.3rem;margin:0 0 14px}.faq-item{border-bottom:1px solid var(--line-soft)}.faq-item:last-child{border-bottom:none}.faq-item summary{cursor:pointer;font-weight:700;font-size:1rem;padding:14px 4px;list-style:none;display:flex;align-items:center;gap:10px;color:var(--ink)}.faq-item summary::-webkit-details-marker{display:none}.faq-item summary:before{content:"+";display:grid;place-items:center;flex:none;width:22px;height:22px;border-radius:7px;background:var(--brand-soft);color:var(--brand);font-weight:800;font-size:1rem}.faq-item[open] summary:before{content:"−"}.faq-item summary:hover{color:var(--brand)}.faq-item p{margin:0;padding:0 4px 16px 36px;color:var(--ink-soft);font-size:.96rem}.compliance-note{background:#fbf8f2;border:1px dashed #d8cfbe;border-radius:var(--radius-sm);padding:14px 18px;margin-bottom:48px;font-size:.88rem;color:var(--ink-soft)}.compliance-note p{margin:0}.footer-note{font-size:.86rem;color:var(--muted)}.site-footer{border-top:1px solid var(--line);background:var(--card);padding:26px 0 40px;margin-top:20px}.site-footer nav{display:flex;flex-wrap:wrap;gap:6px 20px;margin-bottom:12px}.site-footer nav a{color:var(--ink-soft);font-size:.9rem;font-weight:600}.site-footer nav a:hover{color:var(--brand)}.footer-note{font-size:.86rem;color:var(--muted);max-width:760px;margin:0 0 6px}.footer-copy{font-size:.84rem;color:var(--muted);margin:0}@media(max-width:720px){.header-secondary{display:none}}@media(max-width:640px){.calc,.explanation,.faq,.trust{padding:20px 18px}.hero{padding:44px 0 26px}.field-grid{grid-template-columns:1fr}.result-side{grid-template-columns:1fr 1fr}}