:root{color-scheme:light;--page:#fbfaf7;--surface:#fff;--ink:#26323a;--muted:#64727c;--border:#dce2e5;--accent:#17678f;--soft:#eef5f8;--focus:#1d7fa8}
html[data-theme=dark]{color-scheme:dark;--page:#0c1319;--surface:#152029;--ink:#e2eaf0;--muted:#abb8c2;--border:#2d424f;--accent:#8bd0f4;--soft:#1d303d;--focus:#8bd0f4}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:85px}body{margin:0;background:var(--page);color:var(--ink);font:15px/1.68 system-ui,-apple-system,Segoe UI,sans-serif}
a{color:var(--accent)}a:hover{text-decoration:underline}button{font:inherit;color:inherit;cursor:pointer}a:focus-visible,button:focus-visible{outline:2px solid var(--focus);outline-offset:3px}
html[data-lang=en] .lang.zh,html[data-lang=zh] .lang.en{display:none!important}.skip{position:absolute;top:-100px;left:15px;background:var(--surface);z-index:60;padding:10px 15px}.skip:focus{top:66px}
.guide-header{position:sticky;top:0;z-index:30;display:flex;align-items:center;justify-content:space-between;gap:12px;height:62px;padding:0 max(18px,calc((100vw - 1240px)/2));background:var(--surface);border-bottom:1px solid var(--border)}
.brand{text-decoration:none;white-space:nowrap;color:var(--ink);font-family:Georgia,serif;font-weight:bold;font-size:16px}.brand span{margin-left:10px}.header-actions{display:flex;align-items:center;gap:8px}.header-actions button,.back-link{padding:5px 10px;background:var(--surface);color:var(--ink);border:1px solid var(--border);border-radius:6px;text-decoration:none;font-size:12px;font-weight:600}.header-actions button:hover,.back-link:hover{background:var(--soft);text-decoration:none}
.guide-layout{max-width:1240px;margin:0 auto;display:grid;grid-template-columns:236px minmax(0,1fr);gap:44px;padding:35px 22px 75px}
.guide-nav{position:sticky;top:90px;align-self:start;max-height:calc(100vh - 106px);overflow:auto;display:grid;gap:2px;border-right:1px solid var(--border);padding-right:18px}.guide-nav .nav-title{font-size:11px;text-transform:uppercase;letter-spacing:.07em;font-weight:800;color:var(--muted);margin-bottom:10px}.guide-nav a{display:block;padding:6px 8px;border-radius:5px;font-size:12px;line-height:1.35;color:var(--muted);text-decoration:none}.guide-nav a:hover,.guide-nav a:focus-visible{background:var(--soft);color:var(--accent)}
.guide-content{min-width:0;max-width:790px}.intro{padding:14px 0 26px;border-bottom:1px solid var(--border)}.eyebrow{font-size:11px;text-transform:uppercase;letter-spacing:.13em;color:var(--accent);font-weight:800}h1,h2,h3{font-family:Georgia,'Noto Serif',serif;line-height:1.22;color:var(--ink)}h1{font-size:clamp(31px,4vw,45px);margin:5px 0 15px}h2{font-size:25px;margin:0 0 18px}h3{font-size:17px;margin:22px 0 5px}.lead{font-size:17px;color:var(--muted);max-width:64ch}
section{padding:35px 0;border-bottom:1px solid var(--border)}section p{margin:0 0 15px}ol{padding-left:22px;margin:10px 0 21px}li{margin:0 0 10px;padding-left:4px}strong{font-weight:730}.muted{color:var(--muted)}.notice{padding:12px 15px;border-left:3px solid var(--accent);background:var(--soft);border-radius:0 6px 6px 0}
kbd{display:inline-block;padding:1px 5px;white-space:nowrap;font:600 12px/1.6 ui-monospace,SFMono-Regular,Consolas,monospace;border:1px solid var(--border);border-bottom-width:2px;border-radius:4px;background:var(--surface)}
.shortcut-groups{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));column-gap:32px;max-width:700px;margin-top:19px;align-items:start}
.shortcut-column{display:flex;flex-direction:column;gap:21px;min-width:0}
.shortcut-group{min-width:0}.shortcut-group h3{margin:0 0 6px;font:700 11px/1.5 system-ui,-apple-system,Segoe UI,sans-serif;letter-spacing:.055em;text-transform:uppercase;color:var(--muted)}
.shortcut-list{margin:0}.shortcut-row{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:32px;padding:3px 0;font-size:13px;line-height:1.35}
.shortcut-row dt{min-width:0}.shortcut-row dd{flex:none;display:flex;align-items:center;gap:4px;margin:0;white-space:nowrap}.shortcut-row kbd{font-size:11px;background:var(--soft);border-color:var(--border)}.shortcut-sep{color:var(--muted);font-size:11px}
.faq h3{margin-top:18px}.faq p{margin-bottom:14px}.guide-footer{display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;padding:30px 0;color:var(--muted);font-size:12px}
@media(max-width:900px){.guide-layout{grid-template-columns:1fr;gap:8px;padding:20px 22px 65px}.guide-nav{position:relative;top:auto;max-height:none;display:flex;flex-wrap:wrap;gap:3px;border-right:0;border-bottom:1px solid var(--border);padding:0 0 14px}.guide-nav .nav-title{flex-basis:100%;margin-bottom:1px}.guide-nav a{padding:5px 7px}.guide-content{max-width:none}}
@media(max-width:520px){.guide-header{height:55px;padding:0 11px}.guide-header .brand span{display:none}.header-actions{gap:4px}.header-actions button,.back-link{padding:6px;font-size:11px}.guide-layout{padding:15px 16px 55px}section{padding:29px 0}h2{font-size:22px}.shortcut-groups{grid-template-columns:1fr;gap:20px}.shortcut-column{gap:20px}html{scroll-padding-top:65px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}