:root{color-scheme:light;--canvas:#f7f8fa;--paper:#fff;--ink:#172533;--muted:#546679;--accent:#08776b;--line:#dbe2e9;--soft:#e3f1ee}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--canvas);color:var(--ink);font:16px/1.75 system-ui,-apple-system,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif}a{color:var(--accent);text-underline-offset:4px}a:focus-visible{outline:3px solid #79ad99;outline-offset:5px;border-radius:4px}.shell{max-width:1000px;padding:0 30px;margin:auto}.skip{position:absolute;top:-80px;left:20px;padding:10px;background:var(--paper)}.skip:focus{top:10px}header{display:flex;align-items:center;justify-content:space-between;gap:24px;padding:25px 0;border-bottom:1px solid var(--line)}.brand{font-size:20px;font-weight:750;text-decoration:none;letter-spacing:-.5px}nav{display:flex;gap:22px;flex-wrap:wrap;font-size:13px}.hero{padding:58px 0 40px}.eyebrow{font-size:12px;font-weight:750;letter-spacing:.09em;text-transform:uppercase;color:var(--accent)}h1{max-width:850px;font-size:clamp(32px,4.6vw,50px);line-height:1.15;letter-spacing:-1.4px;margin:18px 0 24px}h2{font-size:25px;line-height:1.35;letter-spacing:-.5px;margin:0 0 18px}h3{font-size:18px;line-height:1.45;margin:0 0 10px}p{margin:0 0 17px}.lede{max-width:830px;font-size:18px;color:var(--muted)}.actions{display:flex;gap:12px;flex-wrap:wrap;margin:27px 0 17px}.button{display:inline-flex;align-items:center;justify-content:center;padding:11px 18px;min-height:46px;border:1px solid var(--line);border-radius:9px;background:var(--paper);text-decoration:none;font-size:14px;font-weight:700}.button.primary{background:var(--accent);border-color:var(--accent);color:white}.meta,.note{color:var(--muted);font-size:13px}.facts{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;margin:0 0 40px}.fact{background:var(--paper);border:1px solid var(--line);border-radius:11px;padding:22px}.fact p{color:var(--muted);font-size:14px;margin:0}.section{padding:34px 0;border-top:1px solid var(--line)}.section>p{max-width:840px}.section ul{padding-left:22px}pre{margin:17px 0 20px;padding:20px;border:1px solid var(--line);border-radius:10px;background:var(--paper);font:13px/1.8 ui-monospace,SFMono-Regular,Consolas,monospace;white-space:pre-wrap;overflow-wrap:anywhere}code{font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:.9em}.callout{margin:22px 0;padding:19px 22px;background:var(--soft);border-left:3px solid var(--accent);border-radius:0 8px 8px 0}.callout p:last-child{margin:0}.faq{margin:25px 0;padding:0 0 23px;border-bottom:1px solid var(--line)}.faq:last-child{border:0;padding-bottom:0}.faq p{color:var(--muted);max-width:840px;margin-bottom:0}.chinese{background:var(--paper);border:1px solid var(--line);border-radius:12px;padding:28px;margin:12px 0 35px}.chinese h2{font-size:25px}.chinese h3{margin-top:24px}.chinese pre{background:var(--canvas)}footer{border-top:1px solid var(--line);display:flex;gap:20px;justify-content:space-between;flex-wrap:wrap;padding:25px 0 32px;color:var(--muted);font-size:12px}footer div{display:flex;gap:18px;flex-wrap:wrap}@media(max-width:680px){.shell{padding:0 20px}header{align-items:flex-start;gap:18px}nav{gap:13px;justify-content:flex-end}.hero{padding-top:37px}h1{letter-spacing:-.8px}.lede{font-size:16px}.facts{grid-template-columns:1fr;gap:12px}.fact{padding:19px}.section{padding:27px 0}.chinese{padding:21px}pre{padding:16px;font-size:12px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}