@import "https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@400;500;600;700&display=swap";
:root{--paper:#f7f7f1;--ink:#253d35;--green:#285446;--muted:#81877e;--line:#e0e4da;--rust:#b96547;--pale:#edf0e8;--serif:"Noto Serif SC","Songti SC",SimSun,serif;--ok:#2f6b4f;--ok-bg:#e7f0e9;--ok-line:#b9d4c2;--bad:#a8503a;--bad-bg:#f6e9e4;--bad-line:#e2bfb2;--partial:#a07a2c;--partial-bg:#f5efdf;--partial-line:#e3d3a8;--flag:#b96547;--surface:#fffffd;--shadow-1:0 1px 2px #253d350f,0 4px 16px #253d350d;--r-card:16px;--r-pill:999px;--ease:cubic-bezier(.2,.8,.2,1);--safe-b:env(safe-area-inset-bottom);--safe-t:env(safe-area-inset-top)}*{box-sizing:border-box}body{background:var(--paper);color:var(--ink);margin:0;font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,Microsoft YaHei,sans-serif;font-size:14px}button,input,textarea,select{font:inherit}button,a,input,textarea,select{-webkit-tap-highlight-color:transparent}button{cursor:pointer;color:inherit;background:0 0;border:0;justify-content:center;align-items:center;gap:8px;display:inline-flex}button:disabled{opacity:.45;cursor:not-allowed}a{color:inherit;text-decoration:none}input,textarea,select{border:1px solid var(--line);color:var(--ink);background:#fff;border-radius:7px;outline:none;padding:12px}input:focus,textarea:focus,select:focus{border-color:#678675;box-shadow:0 0 0 3px #2854460b}button:focus-visible,a:focus-visible{outline:2px solid var(--rust);outline-offset:4px}h1,h2,h3,h4,p{margin-top:0}h1,h2,h3{font-family:var(--serif);font-weight:500}p{line-height:1.9}small{font-size:11px}svg{flex-shrink:0}.app{min-height:100vh}.rail{border-right:1px solid var(--line);z-index:20;background:#f1f3ea;flex-direction:column;align-items:center;width:84px;display:flex;position:fixed;inset:0 auto 0 0}.brand{background:var(--green);color:#fff;width:40px;height:44px;font-family:var(--serif);border-radius:5px 5px 15px;margin-top:24px;font-size:25px}.rail-links{flex-direction:column;gap:22px;margin-top:64px;display:flex}.rail-links button,.rail-settings{color:#90978d;border-radius:8px;flex-direction:column;gap:8px;width:64px;padding:13px 2px;font-size:10px}.rail-links .selected{color:var(--green);background:#e2e8dc}.rail-settings{margin-top:auto}.avatar{background:#dbe2d3;border-radius:50%;place-items:center;width:30px;height:30px;margin:20px 0 26px;font-size:12px;display:grid}.shell{margin-left:84px}.topbar{border-bottom:1px solid var(--line);justify-content:space-between;align-items:center;height:82px;padding:0 44px;display:flex}.wordmark{font-family:var(--serif);letter-spacing:4px;align-items:center;gap:18px;font-size:23px;display:flex}.wordmark i{color:#b7bdb0;font-family:sans-serif;font-size:18px;font-style:normal}.wordmark span{letter-spacing:3px;font:12px 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b{color:#c1c7b7}.hero-art{perspective:900px;justify-self:end;width:100%;max-width:470px;height:305px;position:relative}.art-paper{background:#fffefa;border:1px solid #d9dfcf;width:245px;height:284px;padding:28px;position:absolute;top:7px;left:26%;box-shadow:8px 18px 35px #36492d0a}.art-paper.back{background:#e9eddf;top:0;left:34%;transform:rotate(12deg)}.art-paper.back span{letter-spacing:3px;font-size:8px;line-height:1.8}.art-paper.front{background:#fffefa;transform:rotate(-6deg)}.mini-label{letter-spacing:2px;color:#8b927d;font-size:8px}.art-paper svg{width:100%;height:105px;margin:16px 0 8px}.art-paper h3{white-space:nowrap;font-size:14px}.paper-lines{border-top:1px solid #e1e5d6;border-bottom:1px solid #e1e5d6;width:76%;height:13px}.paper-no{letter-spacing:1.6px;color:#9ba38f;font-size:7px;position:absolute;bottom:18px}.orbit{border:1px solid #dfe3d4;border-radius:50%;width:330px;height:200px;position:absolute;top:40px;left:0;transform:rotate(-32deg)}.orbit-b{width:290px;height:160px;top:72px;left:13px;transform:rotate(29deg)}.art-tag{background:var(--green);color:#eef2e5;border-radius:4px;align-items:center;gap:12px;padding:13px 17px;font-size:10px;display:flex;position:absolute;bottom:20px;left:2%;transform:rotate(2deg);box-shadow:0 8px 16px #213b2417}.collection{border-top:1px solid var(--line);padding:25px 0 0}.section-heading{justify-content:space-between;align-items:center;margin-bottom:23px;display:flex}.section-heading .eyebrow{letter-spacing:2px;font-size:9px}.section-heading h2{margin:9px 0 0;font-size:22px}.subtle{color:#7b8674;padding:10px 0;font-size:11px}.paper-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:22px;display:grid}.paper-card{background:#fdfdf8;border:1px solid #dce2d3;border-radius:9px;padding:24px 28px 0;position:relative;overflow:hidden}.card-top{justify-content:space-between;align-items:center;display:flex}.tag{color:#69775e;background:#f2f4eb;border:1px solid #dde2d4;border-radius:4px;padding:5px 9px;font-size:10px;display:inline-flex}.volume{letter-spacing:2px;color:#9da68e;font:10px Georgia,serif}.book-mark{color:#a4b296;background:#edf1e4;border-radius:7px;padding:16px;position:absolute;top:78px;right:30px;transform:rotate(-8deg)}.paper-card h3{letter-spacing:1px;margin:29px 0 12px;font-size:23px}.paper-card p{color:#858b7b;max-width:76%;min-height:42px;margin-bottom:18px;font-size:11px;line-height:1.9}.card-spec{color:#7e8773;gap:22px;padding-bottom:23px;font-size:10px;display:flex}.card-spec span+span{border-left:1px solid #dce1d2;padding-left:22px}.card-action{border-top:1px solid #e1e5d7;align-items:center;gap:15px;display:flex}.card-action>button:first-child{width:100%;color:var(--green);justify-content:space-between;padding:17px 0;font-size:12px;font-weight:600}.paper-card:hover{border-color:#aab99c;transition:all .2s;transform:translateY(-2px);box-shadow:0 5px 20px #1c402007}.exam-card{background:#ecf0e5}.exam-card .tag{background:#e4eadc}.exam-card .book-mark{color:#769164;background:#dfe7d5}.home-bottom{grid-template-columns:1fr 1fr;gap:55px;padding:35px 0;display:grid}.tiny-number{letter-spacing:3px;color:#a77556;font:11px Georgia,serif}.home-bottom h3{margin:12px 0 10px;font-size:17px}.home-bottom p{color:#929787;font-size:10px;line-height:1.9}.scope{border-left:1px solid var(--line);padding-left:28px}.scope strong{font-size:11px;font-weight:500}.scope p{margin:9px 0}.scope small{color:#a29d88;font-size:9px}footer{border-top:1px solid var(--line);color:#949d89;justify-content:space-between;padding:22px 0 25px;font-size:10px;display:flex}.primary,.outline{border-radius:5px;justify-content:center;align-items:center;gap:10px;padding:12px 18px;font-size:12px;display:inline-flex}.primary{background:var(--green);color:#fff}.primary:hover{background:#1a4032}.outline{background:#ffffff80;border:1px solid #d4ddcc}.wide{width:100%;margin-top:12px}.dark-small{background:var(--green);color:#fff;border-radius:4px;padding:9px 12px;font-size:11px}.back{color:#828b7a;justify-content:flex-start;padding:0;font-size:11px}.workspace{grid-template-columns:245px minmax(360px,1fr) 350px;height:calc(100vh - 82px);display:grid}.question-nav{border-right:1px solid var(--line);background:#f1f3eb;flex-direction:column;min-height:0;padding:24px 17px 0;display:flex}.nav-title{margin-top:28px}.nav-title .eyebrow{letter-spacing:1.5px;font-size:8px}.nav-title h2{margin:10px 0 23px;font-size:17px;line-height:1.5}.progress-row{color:#7a8672;justify-content:space-between;align-items:center;font-size:10px;display:flex}.progress-row strong{color:var(--green);font:19px Georgia,serif}.progress-row small{color:#929b84;font:10px 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var(--line);grid-template-columns:80px 1fr 150px;align-items:center;padding:22px 20px;display:grid}.rank-head{color:#929d85;font-size:10px}.rank-row>span{color:#a5ae93;font:23px Georgia,serif}.rank-row strong{font-size:14px;font-weight:500}.rank-row b{color:var(--green);font:25px Georgia,serif}.empty{text-align:center;color:#9aa68a;padding:70px 20px;font-size:12px}.empty-small{color:#9ba38e;padding:22px 12px;font-size:10px}.result-grid{grid-template-columns:1fr 1fr;align-items:start;gap:55px;margin-top:40px;display:grid}.result-stats{gap:50px;margin:25px 0;display:flex}.result-stats strong{font:44px Georgia,serif}.result-stats small{color:#b0b89e;font-size:16px}.result-stats span{color:#94a083;margin-top:10px;font-size:10px;display:block}.small{font-size:10px}.result-actions{gap:14px;margin-top:22px;display:flex}.rank-opt{border-top:1px solid var(--line);margin-top:30px;padding-top:22px}.rank-opt h3{font-size:16px}.rank-opt p{color:#93a082;font-size:10px}.rank-opt 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