:root{--bg:#fafaf7;--paper:#fff;--ink:#24332d;--muted:#747b73;--line:#e1e5de;--green:#2c6650;--soft:#edf2e9}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:25px}body{margin:0;background:var(--bg);color:var(--ink);font-family:Inter,-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;font-size:14px;line-height:1.65}a{color:inherit;text-decoration:none}a:hover{color:var(--green)}button,input,textarea,select{font:inherit}button,a,input,textarea,select,summary{-webkit-tap-highlight-color:transparent}a:focus-visible,button:focus-visible,summary:focus-visible{outline:3px solid #739f7e;outline-offset:4px}header{max-width:1200px;margin:auto;min-height:100px;display:flex;align-items:center;gap:40px;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:12px;font-size:19px;font-weight:650;letter-spacing:1px}.brand small{display:block;font-size:9px;font-weight:500;letter-spacing:2px;color:var(--muted);line-height:1.5}.symbol{display:grid;place-items:center;width:39px;height:39px;background:var(--ink);color:white;font:32px Georgia;border-radius:9px}.brand:hover{color:var(--ink)}nav{display:flex;gap:32px;margin-left:auto;margin-right:20px}nav a{color:var(--muted)}nav a[aria-current]{color:var(--ink);font-weight:600}nav span{font-size:12px}main{max-width:1120px;margin:auto;min-height:72vh}.button{display:inline-flex;align-items:center;justify-content:center;gap:28px;background:var(--green);color:white;border:1px solid var(--green);padding:12px 20px;border-radius:5px;cursor:pointer;font-weight:550;white-space:nowrap}.button:hover{background:#204d3b;color:white}.button.small{padding:9px 16px;font-size:13px}.button.outline{background:transparent;color:var(--ink);border-color:#ced6cc;gap:8px}.button.outline:hover{background:var(--soft)}.button:disabled{opacity:.6;cursor:wait}.hero{position:relative;padding:64px 0 50px;overflow:hidden}.eyebrow{font-size:11px;letter-spacing:1.5px;font-weight:600;color:var(--green);display:flex;align-items:center;gap:9px}.live-dot{display:inline-block;width:6px;height:6px;background:#688d68;border-radius:50%;flex-shrink:0}.hero h1{font-family:Georgia,"Songti SC",SimSun,serif;font-size:47px;font-weight:500;letter-spacing:1px;line-height:1.45;margin:21px 0 17px}.accent{color:#7c986b}.hero p{line-height:1.95;color:var(--muted);font-size:15px}.hero-links{display:flex;align-items:center;gap:28px;margin-top:28px}.hero-links>a:not(.button){font-size:13px}.hero-mark{position:absolute;right:70px;top:40px;width:290px;height:280px;border:1px solid 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266px;gap:44px}.section-title{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-bottom:18px}.section-title h2{margin:0;font-size:19px;font-weight:600}.section-title h2 span{font-size:12px;color:var(--muted);margin-left:9px;font-weight:400}.section-title>.muted{font-size:11px}.filters{display:flex;gap:8px;margin-bottom:12px}.search{display:flex;align-items:center;border:1px solid var(--line);background:white;border-radius:4px;flex:1;min-width:100px}.search span{font-size:25px;color:#929b8e;padding-left:12px;line-height:1}.search input{border:0;width:100%;min-width:0;padding:11px;background:transparent;font-size:12px}.filters select{max-width:120px;font-size:12px}.filters .button{font-size:12px;padding:8px 12px}input,textarea,select{border:1px solid #d9dfd5;padding:10px 12px;border-radius:4px;color:var(--ink);background:white;max-width:100%}input:focus,textarea:focus,select:focus{outline:2px solid #b8ccb8;outline-offset:1px}textarea{resize:vertical;line-height:1.8;min-height:180px}.question-row{padding:26px 0;border-bottom:1px solid var(--line);display:flex;gap:20px}.answer-count{border:1px solid var(--line);height:58px;min-width:49px;display:flex;flex-direction:column;align-items:center;justify-content:center;margin-top:4px;border-radius:4px;color:var(--muted)}.answer-count strong{font-size:18px;font-weight:500;color:var(--ink)}.answer-count span{font-size:10px}.question-content{flex:1;min-width:0}.question-heading{display:flex;align-items:center;gap:10px;font-size:11px}.status{color:var(--green);font-size:11px;display:inline-flex;align-items:center;gap:6px}.status:before{content:"";width:5px;height:5px;border:1px solid #5b8b68;border-radius:50%}.lean-label{font-family:monospace;color:#809274}.question-row h3{font-size:17px;margin:7px 0;font-weight:550;overflow-wrap:anywhere}.excerpt{font-size:12px;color:var(--muted);margin:0 0 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pre{padding:18px;background:#f0f2ec;border:1px solid var(--line);border-radius:5px;overflow:auto;line-height:1.65;font-size:12px;white-space:pre}.prose code,.doc code{font-family:Consolas,"SFMono-Regular",monospace;font-size:.9em}.prose :not(pre)>code,.doc :not(pre)>code{background:#edf0e8;padding:2px 5px;border-radius:3px}.prose blockquote{border-left:3px solid #a6b997;margin-left:0;padding-left:20px;color:var(--muted)}.prose table{display:block;overflow:auto;border-collapse:collapse;max-width:100%}.prose td,.prose th{padding:8px 12px;border:1px solid var(--line)}.attachments{margin:12px 0 24px}.attachments h3{font-size:12px;font-weight:500}.attachments h3 .muted{font-size:10px}.file{border:1px solid var(--line);border-radius:5px;display:flex;justify-content:space-between;align-items:center;padding:12px;margin:7px 0;font-size:12px;gap:8px}.file>div{display:flex;gap:10px;align-items:center;flex-wrap:wrap;min-width:0}.file a{overflow-wrap:anywhere}.file 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p{font-size:12px}#reply{margin-top:25px}#reply>h2{font-size:20px;font-weight:500}.compose{margin-top:26px}.compose label{display:flex;flex-direction:column;gap:8px;margin-bottom:20px;font-size:12px;font-weight:500}.compose label .muted{font-weight:400;font-size:10px}.form-grid{display:grid;grid-template-columns:2fr 1fr;gap:16px}.upload{border:1px dashed #cbd5c3;border-radius:5px;padding:14px;margin:10px 0 18px}.upload summary{cursor:pointer;font-size:12px;color:var(--green)}.upload summary span{float:right;color:var(--muted);font-size:10px}.upload label{margin-top:20px}.upload p{font-size:11px}.form-note{font-size:11px;color:var(--muted);line-height:1.8}.submit-row{display:flex;gap:20px;align-items:center;margin-top:23px}.form-status{font-size:12px}.form-status.error{color:#a64132}.narrow{max-width:760px;margin:40px auto 70px}.narrow>h1{font:34px Georgia,"Songti 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@media(min-width:1500px){header,footer{max-width:1280px}main{max-width:1200px}.hero{padding-top:78px;padding-bottom:60px}.hero h1{font-size:52px}.hero-mark{right:100px;top:65px}}
@media(max-width:1260px){header,footer{margin-left:32px;margin-right:32px}main{margin:0 48px}}
@media(max-width:900px){.columns,.detail-grid{grid-template-columns:minmax(0,1fr) 230px;gap:26px}.hero-mark{right:0;width:240px;height:240px;top:62px}.hero h1{font-size:40px}.hero-mark>span:first-child{font-size:160px}.stats{gap:25px}.stats p{display:none}main{margin:0 32px}.aside-card{padding:18px}}
@media(max-width:700px){header{margin:0 20px;gap:15px;min-height:82px;flex-wrap:wrap;padding:18px 0}nav{order:3;width:100%;margin:0;gap:25px;font-size:12px}.brand{font-size:17px}header>.button{margin-left:auto}.symbol{width:33px;height:33px}main{margin:0 20px}.hero{padding:40px 0 33px}.hero h1{font-size:35px;position:relative;z-index:1}.hero p{font-size:13px;position:relative;z-index:1}.hero-mark{opacity:.35;right:-83px;top:40px}.hero-links{gap:19px}.hero-links .button{padding:10px 15px;font-size:12px}.hero-links>a:not(.button){font-size:12px}.eyebrow{font-size:9px;letter-spacing:1px}.stats{padding:18px 0;margin-bottom:28px;justify-content:space-between;gap:8px}.stats>div{gap:7px}.stats strong{font-size:23px}.stats span{font-size:10px}.columns,.detail-grid{display:block}.columns>aside,.detail-grid>aside{display:none}.section-title>.muted{display:none}.filters{gap:5px}.filters select{max-width:98px;padding:7px}.question-row{gap:13px;padding:22px 0}.question-row h3{font-size:16px}.answer-count{min-width:40px;height:52px}.row-arrow{display:none}.empty{padding:40px 8px}footer{margin:35px 20px 0;padding:22px 0;gap:14px;flex-direction:column}footer>div{gap:10px;font-size:10px}.problem h1{font-size:27px}.breadcrumb{font-size:10px}.prose{font-size:14px}.narrow{margin:30px auto}.narrow>h1{font-size:28px}.file{align-items:flex-start}.file>a{white-space:nowrap}.form-grid{grid-template-columns:1.4fr 1fr}.export-bar{gap:12px}.submit-row{align-items:flex-start;flex-direction:column}}
.prose math[display=block]{display:block;overflow-x:auto;max-width:100%;margin:1.25em 0;padding:.25em 0}.math-error{white-space:pre-wrap;color:#a33}