:root{color-scheme:light dark;--page:#f1f4ea;--surface:#fffbf1;--ink:#263f3d;--muted:#566d63;--line:#c7d4c9;--accent:#286360;--soft:#e0ece4;--warm:#eabb8b}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:6rem}body{margin:0;background:var(--page);color:var(--ink);font:17px/1.75 -apple-system,BlinkMacSystemFont,'Segoe UI','PingFang SC','Hiragino Sans GB',sans-serif;overflow-wrap:anywhere}a{color:var(--accent);text-underline-offset:4px}a:hover{text-decoration-thickness:2px}a:focus-visible,summary:focus-visible{outline:3px solid var(--accent);outline-offset:4px;border-radius:4px}button,a,summary{-webkit-tap-highlight-color:transparent}p{margin:0 0 1.15rem}h1,h2,h3{line-height:1.25;letter-spacing:-.02em;text-wrap:balance}h1{font-size:clamp(2.3rem,5vw,3.6rem);margin:.65rem 0 1rem}h2{font-size:1.55rem;margin:0 0 1.25rem}h3{font-size:1.1rem}.eyebrow{font-size:.8rem;letter-spacing:.1em;font-weight:650;color:var(--muted);text-transform:uppercase}.skip{position:absolute;top:-100px;left:1rem;z-index:20;padding:12px;background:var(--surface)}.skip:focus{top:10px}
.top{background:var(--surface);border-bottom:1px solid var(--line)}.top-inner{max-width:1160px;margin:auto;padding:18px 28px;display:flex;align-items:center;justify-content:space-between;gap:14px;flex-wrap:wrap}.brand{color:var(--ink);text-decoration:none;display:flex;align-items:center;gap:12px;font-weight:650;font-size:1.12rem;min-height:44px}.brand img{width:42px;height:42px;border-radius:12px}.top-nav{display:flex;align-items:center;gap:6px;flex-wrap:wrap}.top-nav a{min-height:44px;padding:9px 12px;border-radius:50px;font-size:.92rem}.top-nav a[aria-current=page]{background:var(--soft);text-decoration:none}.top-nav .language{border:1px solid var(--line);margin-left:6px}.wrap{max-width:1100px;margin:auto;padding:42px 28px 0}.intro{max-width:780px;margin-bottom:38px}.intro .lede{font-size:1.15rem;color:var(--muted);max-width:660px}.pills{display:flex;gap:10px;flex-wrap:wrap}.pill{display:inline-block;background:var(--soft);padding:4px 12px;border-radius:99px;font-size:.86rem}.layout{display:grid;grid-template-columns:225px minmax(0,1fr);gap:40px}.toc{position:sticky;top:24px;align-self:start}.toc summary{font-weight:650;min-height:44px;cursor:pointer}.toc a{display:block;padding:8px 0;min-height:44px;font-size:.94rem}.article section{padding:0 0 32px;margin-bottom:32px;border-bottom:1px solid var(--line);scroll-margin-top:24px}.callout{padding:18px 22px;border-left:3px solid var(--accent);border-radius:0 14px 14px 0;background:var(--surface);margin:22px 0}.callout p:last-child{margin-bottom:0}.contact{display:inline-flex;align-items:center;justify-content:center;padding:10px 20px;min-height:48px;background:var(--accent);color:var(--surface);border-radius:99px;text-decoration:none;font-weight:650}.cards{display:grid;grid-template-columns:1fr 1fr;gap:24px}.card{display:block;color:var(--ink);padding:28px;background:var(--surface);border:1px solid var(--line);border-radius:24px;text-decoration:none}.card:hover{border-color:var(--accent)}.card h2{margin-top:14px}.card p{color:var(--muted)}.card .arrow{color:var(--accent);font-size:.95rem;text-decoration:underline}.footer{max-width:1100px;margin:50px auto 0;padding:24px 28px 32px;border-top:1px solid var(--line);display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;font-size:.86rem;color:var(--muted)}.review{font-size:.85rem;color:var(--muted)}[data-locale]{display:none}html[lang=zh-Hans] [data-locale=zh-Hans],html[lang=en] [data-locale=en]{display:revert}
@media(max-width:760px){.wrap{padding:28px 20px 0}.top-inner{padding:14px 20px}.layout{grid-template-columns:1fr;gap:24px}.toc{position:static;border:1px solid var(--line);padding:12px 18px;border-radius:16px;background:var(--surface)}.toc nav{display:grid;grid-template-columns:1fr 1fr;gap:0 14px}.cards{grid-template-columns:1fr}.top-nav a{padding:8px}.footer{padding:22px 20px}.intro{margin-bottom:24px}}
@media(max-width:380px){.toc nav{grid-template-columns:1fr}.brand img{width:36px;height:36px}.top-nav{gap:0}}
@media(prefers-color-scheme:dark){:root{--page:#192724;--surface:#23332e;--ink:#f5f4e9;--muted:#c0d1c6;--line:#4d6659;--accent:#addbd1;--soft:#304c43}.contact{color:#192724}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
@media print{.top-nav,.toc,.skip{display:none}.layout{display:block}.wrap{padding:0}.footer{margin-top:20px}body{background:white;color:black}.article section{break-inside:avoid}a{color:inherit}}