:root{--paper:#f5f1e8;--paper-2:#ece6da;--ink:#171713;--muted:#68665f;--line:#1c1c18;--blue:#315ee8;--orange:#ff6946;--card:#fbf8f1;--soft:color-mix(in srgb,var(--ink) 18%,transparent);--side:252px;--serif:Georgia,"Times New Roman","Songti SC",SimSun,serif}
html[data-theme=dark]{--paper:#141414;--paper-2:#1d1d1b;--ink:#f3efe7;--muted:#aaa69d;--line:#eee9df;--card:#1a1a18;--blue:#7294ff;--orange:#ff896f}
*{box-sizing:border-box}html{background:var(--paper);scroll-padding-top:104px}body{margin:0;color:var(--ink);font:16px/1.85 Arial,"PingFang SC","Microsoft YaHei",sans-serif;-webkit-font-smoothing:antialiased;background:radial-gradient(color-mix(in srgb,var(--ink) 8%,transparent) .7px,transparent .7px),var(--paper);background-size:18px 18px}::selection{background:var(--blue);color:white}button,input{font:inherit;color:inherit}button{cursor:pointer}a{color:inherit;text-decoration:none}a:hover{color:var(--blue)}button,a,summary{outline-offset:5px}button:focus-visible,a:focus-visible,summary:focus-visible{outline:2px solid var(--blue)}button{background:transparent;border:1px solid var(--ink)}.skip{position:fixed;left:12px;top:-80px;z-index:100;background:var(--ink);color:var(--paper);padding:10px}.skip:focus{top:10px}
.site-header{position:fixed;inset:0 0 auto;height:76px;display:grid;grid-template-columns:var(--side) 1fr auto;align-items:center;gap:28px;padding:0 28px;border-bottom:1px solid var(--soft);background:color-mix(in srgb,var(--paper) 92%,transparent);backdrop-filter:blur(14px);z-index:30}.wordmark{display:flex;align-items:center;gap:11px;width:fit-content}.wordmark-mark{width:39px;height:39px;border-radius:50%;display:grid;place-items:center;background:var(--ink);color:var(--paper);font-size:12px;font-weight:900}.wordmark-copy{display:flex;flex-direction:column;line-height:1.05}.wordmark-copy strong{font-size:14px}.wordmark-copy small{margin-top:5px;color:var(--muted);font:10px/1 ui-monospace,Consolas,monospace;letter-spacing:.1em;text-transform:uppercase}.header-guide{font-size:13px;color:var(--muted)}.header-actions{display:flex;align-items:center;gap:20px}.header-actions>a{font:700 13px/1 ui-monospace,monospace;border-bottom:2px solid var(--blue);padding:6px 0}.theme-toggle{width:36px;height:36px;border-radius:50%;font-size:20px}#menu{display:none;padding:6px 10px;font-size:13px}
#nav{position:fixed;inset:76px auto 0 0;width:var(--side);padding:26px 20px 38px 26px;border-right:1px solid var(--soft);background:var(--paper);overflow:auto;scrollbar-width:thin;z-index:25}.back-blog{display:block;font:700 11px/1.5 ui-monospace,monospace;margin:0 8px 22px;color:var(--muted)}#opensearch{width:100%;display:flex;justify-content:space-between;align-items:center;padding:9px 12px;font-size:13px;background:var(--card);margin-bottom:28px}kbd{font:11px/1 ui-monospace,monospace;color:var(--muted)}.navgroup{color:var(--muted);font-size:11px;font-weight:700;letter-spacing:.07em;margin:27px 9px 9px}#nav>a:not(.back-blog){display:block;padding:7px 10px;font-size:13px;line-height:1.5;border-left:2px solid transparent;margin:2px 0}#nav>a[aria-current=page]{border-left-color:var(--blue);color:var(--blue);background:color-mix(in srgb,var(--blue) 6%,var(--paper));font-weight:700}#nav>a:hover{background:var(--paper-2)}
.reading-layout{max-width:1540px;margin-left:var(--side);padding:123px 46px 40px;display:grid;grid-template-columns:minmax(0,780px) 180px;gap:48px}main{min-width:0}.article-meta{display:flex;justify-content:space-between;gap:18px;flex-wrap:wrap;font:11px/1.6 ui-monospace,Consolas,monospace;letter-spacing:.045em;color:var(--muted);border-bottom:1px solid var(--ink);padding-bottom:16px;margin-bottom:26px}.article-meta span:first-child{color:var(--blue);font-weight:700}article{overflow-wrap:break-word}article h1{font-family:var(--serif);font-size:clamp(34px,3.4vw,51px);font-weight:500;letter-spacing:-.025em;line-height:1.25;margin:0 0 35px;text-wrap:balance}html[lang=zh-CN] article h1{font-weight:600;letter-spacing:0}article h2{font-family:var(--serif);font-size:28px;line-height:1.45;font-weight:600;letter-spacing:-.015em;margin:48px 0 22px;padding-top:20px;border-top:1px solid var(--soft);scroll-margin-top:104px}article h3{font-size:19px;font-weight:650;line-height:1.5;margin:29px 0 15px;scroll-margin-top:104px}article p{margin:0 0 23px}article a{color:var(--blue);text-decoration:underline;text-decoration-color:color-mix(in srgb,var(--blue) 35%,transparent);text-underline-offset:4px}article a:hover{text-decoration-color:var(--blue)}article ul,article ol{padding-left:24px;margin:15px 0 26px}article li{margin:12px 0}article li::marker{color:var(--muted)}article blockquote{margin:26px 0;padding:18px 22px;background:var(--paper-2);border-left:3px solid var(--blue)}blockquote p:last-child{margin:0}article strong{font-weight:700}article code{font:14px/1.6 ui-monospace,monospace;background:var(--paper-2);padding:2px 4px}article pre{overflow:auto;padding:18px;border:1px solid var(--soft);background:var(--paper-2)}article img{max-width:100%;height:auto}article hr{border:0;border-top:1px solid var(--soft);margin:35px 0}article table{width:100%;border-collapse:collapse;font-size:14px}article th,article td{border-bottom:1px solid var(--soft);padding:10px;text-align:left}a[id]{scroll-margin-top:104px}#toc{position:sticky;top:115px;align-self:start;max-height:calc(100vh - 145px);overflow:auto;border-top:3px solid var(--blue);padding-top:17px;font-size:12px}#toc strong{font:700 10px/1.5 ui-monospace,monospace;color:var(--muted);text-transform:uppercase;letter-spacing:.09em;display:block;margin-bottom:18px}#toc a{display:block;line-height:1.65;margin-bottom:13px;color:var(--muted)}#toc a:hover{color:var(--blue)}
.neighbors{margin-top:65px;border-top:1px solid var(--ink);border-bottom:1px solid var(--ink);display:grid;grid-template-columns:1fr 1fr;gap:26px;padding:23px 0}.neighbors a{display:flex;flex-direction:column;font-size:15px;line-height:1.6}.neighbors a:last-child{text-align:right}.neighbors small{color:var(--muted);font:11px/1.6 ui-monospace,monospace;margin-bottom:8px}footer{display:flex;justify-content:space-between;gap:20px;font:11px/1.6 ui-monospace,monospace;color:var(--muted);padding:30px 0 10px}.qa{border-bottom:1px solid var(--soft);scroll-margin-top:104px}.qa summary{padding:20px 34px 20px 0;font-size:16px;line-height:1.7;font-weight:600;cursor:pointer;list-style:none;position:relative}.qa summary::-webkit-details-marker{display:none}.qa summary:after{content:'+';position:absolute;right:8px;top:20px;color:var(--blue);font-weight:400}.qa[open] summary:after{content:'−'}.qa[open] summary{color:var(--blue)}.qa summary:hover{color:var(--blue)}.answer{padding:4px 0 5px}.qa-tools{display:flex;justify-content:space-between;align-items:center;margin:28px 0 0;gap:15px;font:12px/1.6 ui-monospace,monospace;color:var(--muted)}.qa-tools button{padding:8px 12px;font-size:12px;color:var(--ink)}.qa-tools button:hover{background:var(--ink);color:var(--paper)}
.home .reading-layout{grid-template-columns:minmax(0,960px);max-width:1350px}.home #toc{display:none}.home article{counter-reset:section}.home article h1{font-size:clamp(44px,4.5vw,65px);color:var(--blue);margin-bottom:27px}.home article>p{max-width:780px;color:var(--muted)}.home article>p:first-of-type{font-size:19px;color:var(--ink);line-height:1.85}.home-section{counter-increment:section;display:grid;grid-template-columns:200px minmax(0,1fr);gap:0 35px;border-top:1px solid var(--ink);margin:38px 0 0;padding:25px 0 5px}.home-section h2{grid-column:1;grid-row:1/span 12;padding:0;margin:0;border:0;font-size:27px}.home-section h2:before{content:counter(section,decimal-leading-zero);display:block;color:var(--orange);font:700 12px/1.6 ui-monospace,monospace;margin-bottom:14px}.home-section p{grid-column:2;font-size:15px;color:var(--muted);margin-bottom:24px}.home-section strong{display:inline-block;font-size:19px;line-height:1.55;margin-bottom:7px}.home-section strong a{color:var(--ink);text-decoration:none}.home-section strong a:hover{color:var(--blue)}
dialog{border:1px solid var(--ink);padding:0;background:var(--card);color:var(--ink);width:min(720px,calc(100vw - 32px));max-height:80vh;margin-top:10vh;box-shadow:7px 7px 0 var(--ink)}dialog::backdrop{background:#0008}.searchhead{display:flex;gap:12px;align-items:center;padding:18px;border-bottom:1px solid var(--soft)}#searchinput{width:100%;min-width:0;border:0;background:transparent;padding:7px;font-size:16px}#closesearch{padding:7px 10px;font-size:12px;white-space:nowrap}#results{max-height:60vh;overflow:auto;padding:18px;font-size:14px;color:var(--muted)}.result{display:block;padding:15px 10px;border-bottom:1px solid var(--soft)}.result strong{display:block;font-size:16px;color:var(--ink);line-height:1.5}.result span{display:block;margin-top:7px;font-size:13px;line-height:1.7}.result:hover{background:var(--paper-2)}#mobile-search{display:none}.shade{display:none}
@media(min-width:1600px){.reading-layout{margin-left:calc(var(--side) + 3vw)}}
@media(max-width:1200px){.reading-layout{grid-template-columns:minmax(0,780px);padding-left:35px;padding-right:35px}#toc{display:none}.home-section{grid-template-columns:170px minmax(0,1fr);gap:0 26px}}
@media(max-width:800px){.site-header{height:68px;grid-template-columns:1fr auto;padding:0 20px;gap:12px}.header-guide{display:none}.header-actions{gap:15px}#menu{display:block}.wordmark-copy small{font-size:9px}.wordmark-mark{width:34px;height:34px}#nav{inset:68px auto 0 0;width:280px;transform:translateX(-101%);transition:transform .2s ease}.navopen #nav{transform:translateX(0)}.navopen .shade:not([hidden]){display:block;position:fixed;inset:68px 0 0;z-index:24;background:#0006;border:0;width:100%}.reading-layout{display:block;margin:0!important;padding:104px 24px 40px}.article-meta{font-size:10px;gap:10px}article{font-size:16px;line-height:1.95}article h1{font-size:35px;margin-bottom:28px}article h2{font-size:26px}article h3{font-size:19px}.home article h1{font-size:44px}.home article>p:first-of-type{font-size:18px}.home-section{display:block;margin-top:32px;padding-top:23px}.home-section h2{font-size:27px;margin-bottom:25px}.home-section h2:before{display:inline-block;vertical-align:middle;margin:0 12px 0 0}.home-section strong{font-size:19px}#mobile-search{display:block;position:fixed;bottom:20px;right:20px;z-index:20;background:var(--ink);color:var(--paper);border:1px solid var(--paper);box-shadow:3px 3px 0 var(--blue);padding:9px 15px;font-size:13px}footer{padding-bottom:55px}.neighbors{gap:20px}.neighbors a{font-size:14px}}
@media(max-width:380px){.site-header{padding:0 14px}.wordmark-copy small{display:none}.header-actions{gap:10px}.reading-layout{padding-left:18px;padding-right:18px}.home article h1{font-size:38px}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}
@media print{body{background:white;color:black}.site-header,#nav,#toc,#mobile-search,.qa-tools,.neighbors,footer{display:none}.reading-layout{display:block;margin:0;padding:0}article{font-size:11pt}article h1{font-size:24pt}.qa .answer{display:block}}
:root{--paper:#f7f9f5;--paper-2:#edf2e9;--ink:#26382c;--muted:#657367;--line:#456049;--blue:#416d46;--orange:#81955d;--card:#fff;--serif:Georgia,"Songti SC",SimSun,serif}
html[data-theme=dark]{--paper:#171e18;--paper-2:#202c22;--ink:#e3ecdf;--muted:#a4b49f;--line:#a5b99c;--blue:#a8cc95;--orange:#c1cc95;--card:#1c271e}
body{background:var(--paper)}.club-logo{width:48px;height:48px;object-fit:contain}.wordmark-copy small{font-size:11px;letter-spacing:.02em}.home-logo{float:right;width:132px;height:auto;margin:0 0 20px 24px}article h1{color:var(--ink)}.paper-card{box-shadow:0 2px 7px #26382c0b;border-radius:6px}.paper-card:hover{box-shadow:0 5px 14px #26382c15}.concept-figure{box-shadow:none;border-radius:6px}.home-section{clear:both}html[data-theme=dark] .ama-primary{color:#172018!important}@media(max-width:600px){.home-logo{width:90px;margin-left:14px}.club-logo{width:38px;height:38px}.wordmark-copy small{font-size:10px}}

/* AI chronicle film */
.chronicle-video{display:block;width:100%;height:auto;aspect-ratio:16/9;object-fit:contain;background:#f5f1e8;border:1px solid #c8c3b9;border-radius:12px;margin:1.2rem 0}.chronicle-video::cue{background:rgba(245,241,232,.94);color:#171713}