:root{--blue:var(--color-brand);--navy:var(--color-surface-navy);--ink:var(--color-text-primary);--body:var(--color-text-body);--muted:var(--color-text-secondary);--line:var(--color-border);--paper:var(--color-surface-card);--warm:var(--color-surface-page);--warm2:var(--color-surface-muted)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--warm);color:var(--body);font:400 16px/1.75 "Noto Sans SC","PingFang SC","Microsoft YaHei",sans-serif}a{color:inherit}.shell{width:min(1200px,calc(100% - 32px));margin:auto}.nav{position:sticky;top:0;z-index:20;background:var(--color-overlay-white-96);backdrop-filter:blur(8px);border-bottom:1px solid var(--color-border-subtle)}.nav__inner{height:64px;display:flex;align-items:center;gap:16px}.brand{display:flex;align-items:center;gap:8px;text-decoration:none;color:var(--ink)}.brand__mark{width:30px;height:30px;display:grid;place-items:center;border-radius:8px;background:var(--blue);color:var(--color-text-on-dark);font-weight:500}.brand__text{display:flex;flex-direction:column;line-height:1.2}.brand__name{font-size:14px;font-weight:500}.brand__sub{font-size:10px;color:var(--color-text-muted)}.nav__links{margin-left:auto;display:flex;align-items:center;gap:4px}.nav__item{height:48px;display:flex;align-items:center;padding:0 12px;text-decoration:none;font-size:14px;color:var(--color-text-nav)}.nav__item--active{color:var(--blue);font-weight:500}.btn{display:inline-flex;min-height:44px;align-items:center;justify-content:center;padding:0 20px;border:0;border-radius:8px;text-decoration:none;font:500 14px/1 inherit;cursor:pointer}.btn--primary{background:var(--blue);color:var(--color-text-on-dark)}.nav__cta{margin-left:4px}.nav__burger{display:none;margin-left:auto;width:44px;height:44px;border:0;background:transparent;font-size:24px}.drawer{position:fixed;inset:0;visibility:hidden;pointer-events:none;z-index:30}.drawer.is-open{visibility:visible;pointer-events:auto}.drawer__backdrop{position:absolute;inset:0;background:var(--color-overlay-scrim)}.drawer__panel{position:absolute;right:0;top:0;bottom:0;width:min(320px,84vw);padding:20px;background:var(--color-surface-card);box-shadow:0 20px 50px var(--color-overlay-black-18);transform:translateX(100%);transition:transform .25s}.drawer.is-open .drawer__panel{transform:translateX(0)}.drawer__head{display:flex;justify-content:space-between;align-items:center;margin-bottom:12px}.drawer__close{width:40px;height:40px;border:0;background:none;font-size:25px}.drawer__link{display:flex;justify-content:space-between;align-items:center;height:48px;border-bottom:1px solid var(--warm2);text-decoration:none}.drawer__cta{margin-top:24px;width:100%}.drawer__cta .btn{width:100%}.hero-band{position:relative;overflow:hidden;background:var(--color-surface-dark);color:var(--color-text-on-dark);border-bottom:1px solid var(--color-overlay-white-08)}.hero-band:before{content:"";position:absolute;inset:0;background:radial-gradient(circle at 80% 20%,var(--color-overlay-brand-glow),transparent 50%),radial-gradient(circle at 10% 85%,var(--color-overlay-amber-glow),transparent 45%)}.hero-band>.shell{position:relative}.crumb{margin:0;padding:22px 0 12px;color:var(--color-text-on-dark-muted);font-size:14px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.crumb a{text-decoration:none}.crumb span{padding:0 7px;color:var(--color-text-on-dark-subtle)}.hero{min-height:400px;padding:48px 0 56px}.eyebrow{margin:0 0 12px;color:var(--color-brand-soft);font-size:14px}.hero h1{max-width:1008px;margin:0;color:var(--color-text-on-dark);font-size:40px;font-weight:500;line-height:1.2;letter-spacing:-.3px}.hero-answer{max-width:880px;margin:22px 0;color:var(--color-text-on-dark-secondary)}.reading-focus{display:flex;flex-wrap:wrap;align-items:center;gap:8px;margin:22px 0 28px}.reading-focus strong{font-size:14px}.chip{border:1px solid var(--color-overlay-white-18);border-radius:999px;padding:5px 10px;background:var(--color-overlay-white-10);color:var(--color-text-on-dark-band);font-size:13px}.main-grid{display:grid;grid-template-columns:200px minmax(0,760px);gap:48px;align-items:start;padding:44px 0 80px}.toc{position:sticky;top:88px;border-left:2px solid var(--line);padding-left:15px;font-size:13px;color:var(--muted)}.toc strong{display:block;margin-bottom:9px;color:var(--ink);font-weight:500}.toc a{display:block;margin:7px 0;text-decoration:none}.body-section{padding:38px 0;border-bottom:1px solid var(--line);scroll-margin-top:90px}.body-section:first-child{padding-top:0}.body-section h2{margin:0 0 18px;color:var(--ink);font-size:30px;font-weight:500;line-height:1.35}.body-section h3{margin:28px 0 10px;color:var(--ink);font-size:19px;font-weight:500;line-height:1.45}.body-section p{margin:14px 0}.body-section ul,.body-section ol{margin:16px 0;padding-left:1.35em}.body-section li{margin:8px 0}.service{padding:80px 0;background:var(--navy);color:var(--color-text-on-dark)}.service .tag{display:inline-block;border-radius:999px;padding:5px 10px;background:var(--color-overlay-brand-tint);color:var(--color-brand-soft);font-size:12px}.service h2{margin:12px 0 10px;color:var(--color-text-on-dark);font-size:28px;font-weight:500}.service p{max-width:720px;margin:0;color:var(--color-border-subtle)}.service .btn{margin-top:24px}.faq{padding:72px 0}.faq-inner{width:min(760px,calc(100% - 32px));margin:auto}.faq h2{margin:0 0 18px;color:var(--ink);font-size:28px;font-weight:500}.faq details{border-top:1px solid var(--line)}.faq details:last-child{border-bottom:1px solid var(--line)}.faq summary{display:flex;align-items:center;min-height:56px;cursor:pointer;color:var(--ink);font-weight:500}.faq p{padding:0 0 16px;margin:0;color:var(--muted)}.faq a{color:var(--color-link)}.empty-related{display:none}footer{padding:0px 0 0px;background:var(--color-surface-band);color:var(--color-band-line-2);font-size:14px}.footer-top{display:grid;grid-template-columns:2.05fr repeat(5,1fr);gap:30px;padding-bottom:40px}.footer-brand{max-width:230px}.footer-brand-top{display:flex;align-items:center;gap:10px;color:var(--color-text-on-dark);font-weight:600}.footer-mark{display:grid;place-items:center;width:30px;height:30px;border-radius:8px;background:var(--color-brand-cta);font-size:16px}.footer-brand small{display:block;color:var(--color-text-on-dark-faint);font-size:11px;font-weight:400}.footer-brand p{margin:18px 0 0;color:var(--color-band-line);line-height:1.65}.footer-column strong{display:block;margin:4px 0 14px;color:var(--color-text-on-dark)}.footer-column a{display:block;margin:10px 0;color:var(--color-band-surface);text-decoration:none;white-space:nowrap}.footer-bottom{display:flex;justify-content:space-between;gap:24px;padding-top:20px;border-top:1px solid var(--color-overlay-white-14);color:var(--color-band-line-3);font-size:12px}.footer-legal{display:flex;flex-wrap:wrap;gap:20px}.footer-legal a{color:inherit;text-decoration:none}@media(max-width:991px){.nav__links,.nav__cta{display:none}.nav__burger{display:block}.hero{min-height:360px;padding:36px 0 48px}.hero h1{font-size:32px}.main-grid{grid-template-columns:1fr;gap:22px}.toc{position:static;border:1px solid var(--line);border-radius:12px;padding:14px 16px;background:var(--color-surface-card)}.toc a{display:none}.toc a:first-of-type{display:block}.footer-top{grid-template-columns:repeat(3,1fr)}.footer-brand{grid-column:span 3;max-width:420px}}@media(max-width:767px){body{font-size:14px}.nav__inner{height:56px}.crumb{font-size:12px}.hero{min-height:320px;padding:28px 0 40px}.hero h1{font-size:28px}.hero-answer{font-size:15px}.main-grid{padding:28px 0 52px}.body-section{padding:30px 0}.body-section h2{font-size:23px}.body-section h3{font-size:18px}.service,.faq{padding:52px 0}.service h2,.faq h2{font-size:22px}.footer-top{grid-template-columns:repeat(2,1fr);gap:24px 18px;padding-bottom:32px}.footer-brand{grid-column:span 2}.footer-bottom{display:block}.footer-legal{margin-top:14px;gap:14px}}