:root{--bg:#0b1020;--surface:#fff;--surface-muted:#f6f8fb;--text:#111827;--muted:#6b7280;--line:#e5e7eb;--primary:#2563eb;--accent:#ff5a5f;--success:#16a34a;--warning:#f59e0b;--error:#dc2626}*{box-sizing:border-box}html{scroll-behavior:smooth}body{color:var(--text);background:#f8fafc;margin:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}a{color:inherit;text-decoration:none}button,input,select{font:inherit}.skip-link{z-index:100;background:#fff;padding:8px;position:absolute;top:8px;left:-999px}.skip-link:focus{left:8px}.header{z-index:50;-webkit-backdrop-filter:blur(16px);backdrop-filter:blur(16px);color:#fff;background:#0b1020db;border-bottom:1px solid #ffffff14;position:sticky;top:0}.nav{align-items:center;gap:22px;max-width:1180px;min-height:68px;margin:0 auto;padding:0 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56px;display:grid}.eyebrow{color:#bfdbfe;text-transform:uppercase;letter-spacing:.12em;font-size:12px;font-weight:800}h1{letter-spacing:-.06em;text-wrap:balance;margin:14px 0;font-size:clamp(36px,5vw,62px);line-height:1.02}.headline-line{display:block}.subhead{color:#dbeafe;max-width:640px;font-size:18px;line-height:1.65}html[data-lang=zh] body{font-family:PingFang SC,Noto Sans SC,Microsoft YaHei,Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}html[data-lang=zh] h1{letter-spacing:-.025em;max-width:760px;font-size:clamp(34px,4.05vw,52px);font-weight:850;line-height:1.2}html[data-lang=zh] .subhead{letter-spacing:.01em;max-width:680px;font-size:17px;line-height:1.85}html[data-lang=zh] .eyebrow{letter-spacing:.08em}html[data-lang=zh] .badge{letter-spacing:.01em}.badges{flex-wrap:wrap;gap:10px;margin:22px 0;display:flex}.badge{color:#fff;background:#ffffff14;border:1px solid #ffffff29;border-radius:999px;align-items:center;gap:7px;padding:8px 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label{margin-bottom:8px;font-size:14px;font-weight:800;display:block}.segment{grid-template-columns:repeat(2,1fr);gap:8px;display:grid}.segment.three{grid-template-columns:repeat(3,1fr)}.option{border:1px solid var(--line);cursor:pointer;text-align:left;background:#fff;border-radius:14px;padding:10px;font-weight:700}.option.active{border-color:var(--primary);color:#1d4ed8;background:#eff6ff}.progress{gap:10px;display:grid}.step{color:#475569;background:#f8fafc;border-radius:14px;align-items:center;gap:10px;padding:10px;display:flex}.dot{background:#cbd5e1;border-radius:999px;width:10px;height:10px}.step.active .dot{background:var(--primary);box-shadow:0 0 0 5px #dbeafe}.step.done .dot{background:var(--success)}.alert{color:#991b1b;background:#fef2f2;border:1px solid #fecaca;border-radius:14px;margin:12px 0;padding:12px}.result{gap:14px;display:grid}.compare{grid-template-columns:1fr 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