@charset "UTF-8";
:root{--bg:#f4f6fa;--paper:#fff;--ink:#1c2742;--muted:#6d778d;--line:#e5e9f1;--blue:#2a4ee8;--light:#edf1ff;--green:#14785c;--red:#bc3851;--radius:16px;font-family:Inter,"Microsoft YaHei","PingFang SC",sans-serif;color:var(--ink);font-size:16px;line-height:1.7;background:var(--bg)}*{box-sizing:border-box}body{margin:0}a{color:inherit;text-decoration:none}button,input,select{font:inherit}button,a,input,select,summary{outline-offset:4px}button{cursor:pointer}button:disabled{cursor:default;opacity:.5}.shell{display:flex;min-height:100vh}aside{width:244px;position:fixed;inset:0 auto 0 0;background:white;border-right:1px solid var(--line);padding:35px 22px;display:flex;flex-direction:column}.brand{display:flex;gap:12px;align-items:center;font-size:24px;font-weight:750;letter-spacing:2px}.brand-mark{background:var(--blue);color:#fff;border-radius:13px;padding:4px 12px;font-size:27px}.brand small{display:block;font-weight:400;font-size:12px;letter-spacing:1px;color:var(--muted)}.nav-label{font-size:12px;color:#8b94a6;margin:45px 16px 13px}nav{display:grid;gap:7px}nav a{display:flex;align-items:center;gap:14px;padding:12px 16px;border-radius:10px;color:#637087;font-size:18px}nav a span{font-size:15px}nav a:hover,nav a.active{background:var(--light);color:var(--blue)}nav a.active{font-weight:650}.sidebar-foot{margin-top:auto;padding:36px 15px 0;font-size:14px;color:var(--muted)}.sidebar-foot a{color:var(--blue)}.workspace{margin-left:244px;width:calc(100% - 244px)}header{height:78px;padding:0 48px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);background:#ffffffb8;font-size:14px;color:var(--muted)}header strong{color:var(--ink);font-weight:500}.header-right{display:flex;gap:22px;align-items:center}.avatar{width:34px;height:34px;text-align:center;border:1px solid var(--line);border-radius:50%;background:#fff;line-height:32px}main{max-width:1320px;margin:auto;padding:40px 48px 55px;min-height:calc(100vh - 140px)}h1{font-size:30px;line-height:1.4;margin:8px 0 12px;letter-spacing:-.6px}h2{font-size:21px;line-height:1.5;margin:26px 0 17px}h3{font-size:18px;line-height:1.5;margin:12px 0}p{margin:10px 0 18px}.eyebrow{color:var(--blue);font-size:13px;font-weight:600;letter-spacing:1px}.muted{color:var(--muted)}.tag{display:inline-block;font-size:12px;background:var(--light);color:var(--blue);border-radius:5px;padding:3px 9px}.tag.gray{background:#f0f2f6;color:#747e91}.hero-card{margin:27px 0;background:#eaf0ff;border:1px solid #dce5ff;border-radius:var(--radius);padding:30px 34px;display:flex;justify-content:space-between;gap:20px;align-items:center;overflow:hidden}.hero-card h2{font-size:28px;margin:12px 0}.hero-card p{color:#596986}.stack-art{min-width:210px;display:grid;text-align:center;gap:5px;padding:0 15px}.stack-art span{font-size:13px;color:#4c65a1}.stack-art b{background:#fff;border:1px solid #cad7ff;border-radius:5px;padding:2px;color:#3654bb;box-shadow:4px 4px 0 #d8e1ff}.stack-art small{font-size:10px;letter-spacing:2px;margin-top:8px;color:#7c8db5}.btn{display:inline-flex;gap:8px;align-items:center;justify-content:center;background:white;color:var(--ink);border:1px solid #dce1eb;border-radius:8px;padding:9px 17px;font-weight:500;font-size:14px;line-height:1.6}.btn:hover{border-color:var(--blue);color:var(--blue)}.btn.primary{background:var(--blue);color:#fff;border-color:var(--blue)}.btn.danger{color:var(--red)}.btn.small{padding:5px 11px;font-size:13px}.grid-three{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:19px}.grid-two{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.card{background:white;border:1px solid var(--line);border-radius:var(--radius);padding:23px}.card p{font-size:14px;color:var(--muted)}.card .card-bottom{margin-top:20px;display:flex;justify-content:space-between;align-items:center;font-size:13px;color:var(--muted)}.metrics{display:grid;grid-template-columns:repeat(4,1fr);gap:15px;margin:27px 0}.metric{padding:19px 22px;border:1px solid var(--line);border-radius:12px;background:white}.metric span{display:block;color:var(--muted);font-size:13px}.metric b{font-size:28px;line-height:1.8;font-weight:650}.metric small{font-size:14px;margin-left:6px;color:var(--muted)}.section-head{display:flex;align-items:center;justify-content:space-between;gap:15px;margin:28px 0 16px}.section-head h2{margin:0}.section-head a{font-size:14px;color:var(--blue)}.progress{height:6px;background:#e9edf5;border-radius:5px;overflow:hidden}.progress i{display:block;height:100%;background:var(--blue);border-radius:5px}.notice{border-left:3px solid #96aaed;padding:11px 16px;background:#edf1fb;color:#596983;font-size:14px;margin:20px 0}.rows{display:grid;gap:10px}.row{display:flex;gap:14px;justify-content:space-between;align-items:center;padding:15px 18px;background:white;border:1px solid var(--line);border-radius:10px}.row strong{font-size:15px}.row small{display:block;color:var(--muted);font-size:13px}.row .number{font-family:monospace;color:#93a0b9;margin-right:12px}.subject{margin:18px 0;background:white;border:1px solid var(--line);border-radius:12px;overflow:hidden}.subject summary{padding:18px 22px;cursor:pointer;font-weight:650}.subject .rows{padding:0 20px 20px}.subject .row{background:#fafbfe}.lesson-layout{display:grid;grid-template-columns:minmax(0,1fr) 240px;gap:25px}.prose{background:white;border:1px solid var(--line);border-radius:var(--radius);padding:28px 34px;font-size:16px;overflow:hidden}.prose h2{border-top:1px solid var(--line);padding-top:25px;margin-top:28px}.prose h2:first-child{border-top:0;margin-top:0;padding-top:0}.prose p{line-height:1.95}.prose li{margin:8px 0}.prose code,code{font-family:Consolas,monospace;background:#eef2fa;padding:2px 5px;border-radius:4px;font-size:.94em}pre{background:#17243d;color:#e1e9ff;padding:20px;border-radius:10px;overflow:auto;font-size:14px;line-height:1.8;white-space:pre}pre code{background:transparent;padding:0;color:inherit}.table-wrap{overflow:auto}table{border-collapse:collapse;width:100%;font-size:14px;text-align:left}th,td{padding:10px 12px;border-bottom:1px solid var(--line);white-space:normal}th{background:#f5f7fc}details.example{border:1px solid #dce4fc;border-radius:10px;padding:15px 18px;margin:17px 0;background:#f9faff}details.example summary{cursor:pointer;color:var(--blue);font-weight:600}.lesson-side{align-self:start;position:sticky;top:24px}.lesson-side a{display:block;font-size:14px;padding:9px 0;color:var(--muted)}.lesson-side a.current{color:var(--blue);font-weight:650}.actions{display:flex;gap:10px;flex-wrap:wrap;margin:20px 0}.filters{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin:23px 0}select,input[type=search]{border:1px solid #dce1eb;background:white;border-radius:8px;padding:10px 13px;color:var(--ink);max-width:100%}.question-card{background:white;border:1px solid var(--line);border-radius:16px;padding:28px;max-width:900px;margin:20px auto}.question-meta{display:flex;justify-content:space-between;gap:12px;font-size:13px;color:var(--muted)}.question-title{font-size:19px;margin:22px 0;white-space:pre-wrap;line-height:1.9}.options{display:grid;gap:12px}.option{width:100%;text-align:left;border:1px solid #dfe4ed;background:white;border-radius:10px;padding:14px 18px;display:flex;gap:14px;color:var(--ink);align-items:center}.option b{font-weight:500;border:1px solid var(--line);border-radius:6px;width:30px;min-width:30px;text-align:center;line-height:28px;color:var(--muted)}.option.selected{background:#edf1ff;border-color:var(--blue)}.option.correct{background:#edf8f3;border-color:#66ae92}.option.wrong{background:#fff1f3;border-color:#d58090}.option:disabled{opacity:1}.feedback{margin:24px 0 0;padding:18px;border-radius:10px;background:#f2f6ff;font-size:15px}.feedback h3{margin:0 0 9px}.feedback p{margin-bottom:8px;white-space:pre-wrap}.feedback.good h3{color:var(--green)}.feedback.bad h3{color:var(--red)}.empty{text-align:center;padding:50px 20px;background:white;border:1px solid var(--line);border-radius:16px}.empty b{font-size:22px;display:block}.empty p{color:var(--muted)}.simulation{background:#f5f7fd;border:1px solid #e0e6f5;border-radius:12px;padding:20px;margin:20px 0}.cells{display:flex;gap:7px;flex-wrap:wrap;margin:16px 0}.cell{width:49px;min-height:55px;background:white;border:1px solid #d8dfed;border-radius:7px;text-align:center;padding:3px}.cell.filled{background:#e4ebff;border-color:#9cafea;color:var(--blue)}.cell small{display:block;font-size:11px;color:var(--muted)}.cell b{font-size:17px}.sim-status{min-height:30px;font-size:14px}.bars{height:135px;display:flex;align-items:end;gap:12px;padding-top:15px}.bar{flex:1;background:#5675ed;border-radius:5px 5px 0 0;display:flex;align-items:start;justify-content:center;color:#fff;font-size:14px;padding-top:5px}.bar.hot{background:#e69a32}.back{color:var(--blue);font-size:14px}footer{padding:20px 48px;font-size:12px;color:#929aaa;display:flex;justify-content:space-between;border-top:1px solid var(--line)}#toast{position:fixed;bottom:25px;left:50%;transform:translateX(-50%);background:#1c2742;color:white;border-radius:10px;padding:12px 20px;box-shadow:0 5px 25px #17243d25;z-index:30;display:none;max-width:90vw;font-size:14px}.hidden{display:none!important}.file-label{cursor:pointer}.warning{color:var(--red)}.read-badge{color:var(--green);font-size:13px} @media(min-width:1550px){main{padding-top:50px}.hero-card{padding:35px 42px}}@media(max-width:1100px){aside{width:205px;padding:28px 15px}.workspace{margin-left:205px;width:calc(100% - 205px)}main{padding:30px 25px}header{padding:0 25px}.lesson-layout{grid-template-columns:1fr}.lesson-side{position:static}.grid-three{gap:12px}.card{padding:18px}.metrics{gap:10px}.metric{padding:15px}}@media(max-width:760px){aside{position:static;width:100%;padding:18px 18px 8px;border:0;border-bottom:1px solid var(--line)}.shell{display:block}.brand{font-size:21px}.brand-mark{font-size:22px}.nav-label,.sidebar-foot{display:none}nav{display:flex;gap:3px;margin-top:18px;overflow:auto}nav a{padding:9px;gap:5px;white-space:nowrap;font-size:15px}nav a span{font-size:13px}.workspace{margin:0;width:100%}header{height:52px;padding:0 20px;font-size:12px}.header-right{gap:10px}.avatar{display:none}main{padding:26px 18px 35px}h1{font-size:25px}.hero-card{padding:23px;gap:10px}.hero-card h2{font-size:24px}.stack-art{display:none}.grid-three,.grid-two{grid-template-columns:1fr}.metrics{grid-template-columns:repeat(2,1fr)}.metric b{font-size:25px}.card{padding:21px}.prose{padding:21px}.question-card{padding:20px}.question-title{font-size:17px}.row{padding:12px;flex-wrap:wrap}.row>div{flex:1;min-width:180px}.subject .rows{padding:0 12px 12px}.subject summary{padding:16px}.filters{align-items:stretch}.filters select{width:100%}footer{padding:16px 20px;display:block}footer span{display:block}.header-right{font-size:11px}.lesson-side{display:none}}@media(prefers-reduced-motion:no-preference){.btn,.option,nav a{transition:background .15s,border-color .15s}main{animation:appear .2s ease}@keyframes appear{from{opacity:.6}to{opacity:1}}}