:root{--ink: #171918;--paper: #f2eee4;--red: #a43228;--line: #d2cbbd;--muted: #676459;--serif: "Noto Serif SC", "Songti SC", "SimSun", serif;--sans: "Microsoft YaHei", "PingFang SC", system-ui, sans-serif;--mono: ui-monospace, "Cascadia Code", monospace;font-family:var(--sans);color:var(--paper);background:var(--ink);font-synthesis:none}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:30px}body{margin:0;font-size:16px;line-height:1.8}button,input{font:inherit}button{cursor:pointer}button:disabled{cursor:default;opacity:.6}a{color:inherit}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #d9a745;outline-offset:4px}.skip{position:absolute;top:-100px;left:20px;padding:10px;background:var(--paper);color:var(--ink);z-index:10}.skip:focus{top:10px}.masthead{max-width:1440px;margin:auto;padding:24px 48px;border-bottom:1px solid #43453f;display:flex;justify-content:space-between;align-items:center;gap:20px}.brand{display:flex;align-items:center;gap:16px}.mark{border:1px solid #bbb9ae;font:24px/43px var(--serif);width:45px;height:45px;text-align:center}.brand-name{font:700 18px var(--serif);letter-spacing:.15em}.brand small{display:block;font:12px var(--mono);letter-spacing:.18em;color:#c0bfb3;margin-top:6px}.mast-meta{text-align:right;color:#c0bfb3;font:13px/1.8 var(--mono)}.mast-meta span{display:block}.layout{max-width:1440px;margin:auto;display:grid;grid-template-columns:280px minmax(0,1fr);gap:48px;padding:40px 48px 64px}.sidebar{align-self:start;position:sticky;top:28px}.eyebrow{font:12px var(--mono);letter-spacing:.14em;color:#b2b2a5}.sidebar h1{font:700 32px/1.45 var(--serif);letter-spacing:.06em;margin:12px 0 18px}.intro{font-size:15px;color:#c5c3b7;line-height:1.9;margin-bottom:32px}.index-label{font-size:14px;color:#b8b7ab;border-bottom:1px solid #45463f;padding-bottom:10px;display:flex;justify-content:space-between}.nav{display:grid;margin-top:8px}.nav a{padding:14px 0;text-decoration:none;border-bottom:1px solid #353730;display:grid;grid-template-columns:30px 1fr;column-gap:10px}.nav a:hover .nav-title{color:#f6c5a9}.nav-number{font:14px var(--mono);padding-top:5px;color:#b5b2a3}.nav-title{font-size:15px}.nav-status{grid-column:2;color:#a5a69a;font-size:12px}.nav a.solved .nav-status{color:#efbd8d}.progress{margin-top:30px}.progress-line{display:flex;justify-content:space-between;font-size:14px;color:#c6c5b8;gap:10px}.progress-track{height:3px;background:#45463e;margin-top:13px}.progress-track div{height:100%;background:#d9ac83;transition:width .3s}.side-note{color:#a9a99b;font-size:13px;margin-top:26px;border-left:2px solid #706c59;padding-left:13px}.final-link{display:inline-block;font-size:14px;color:#d9bd9d;text-underline-offset:5px;margin-top:14px}.content{min-width:0}.document{background:var(--paper);color:var(--ink);padding:38px 48px;margin-bottom:28px;border-top:3px solid #b8a68a;box-shadow:0 10px 40px #00000014}.doc-top{display:flex;justify-content:space-between;align-items:center;gap:15px;font:12px var(--mono);letter-spacing:.09em;color:var(--muted);border-bottom:1px solid var(--line);padding-bottom:16px}.stamp{border:1px solid var(--red);color:var(--red);padding:2px 9px;font:13px var(--sans);letter-spacing:.12em;white-space:nowrap}.document h2{font:700 32px/1.5 var(--serif);margin:22px 0 7px;letter-spacing:.03em}.subtitle{color:var(--muted);font-size:14px;margin:0 0 26px}.puzzle-body p{margin:16px 0}.puzzle-body ul,.puzzle-body ol{padding-left:24px}.puzzle-body li{margin:7px 0}.evidence{border-left:3px solid #958a75;background:#e8e2d6;padding:18px 22px;margin:24px 0}.evidence span{font-size:12px;letter-spacing:.08em;color:#6c6253}.evidence p,.evidence ul,.evidence ol{margin:9px 0 0}.table-wrap{overflow-x:auto;margin:24px 0}table{width:100%;border-collapse:collapse;text-align:left;font-size:15px}th{color:#6f6658;font-size:14px;font-weight:500;background:#e7e1d6}th,td{padding:11px 14px;border-bottom:1px solid var(--line)}th:first-child,td:first-child{white-space:nowrap}.question{font-weight:600;border-top:1px solid var(--line);padding-top:22px}.testimonies{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:24px 0}.testimonies blockquote{margin:0;border:1px solid var(--line);padding:16px 18px}.testimonies span{font-size:12px;color:var(--muted)}.testimonies p{font:18px/1.8 var(--serif);margin:7px 0 0}.answer-area{padding-top:22px;border-top:1px dashed #c3baa8;margin-top:26px}.answer-area label{display:block;font-size:14px;margin-bottom:10px;color:var(--muted)}.answer-controls{display:flex;gap:12px;align-items:stretch;flex-wrap:wrap}.digit{width:80px;min-width:0;border:1px solid #a49b89;background:#fbf8f1;color:var(--ink);font:24px var(--mono);text-align:center;padding:10px;border-radius:0}.verify-button{border:0;background:var(--ink);color:var(--paper);padding:12px 22px;font-size:14px;letter-spacing:.08em}.verify-button:hover{background:#353931}.feedback{font-size:14px;min-height:25px;margin:10px 0 0;color:var(--red)}.feedback.correct{color:#426044}.explanation{background:#e4e7da;border-left:3px solid #5a6b49;padding:16px 20px;margin-top:16px;font-size:15px}.explanation strong{display:block;font:700 18px var(--serif);margin-bottom:6px}.explanation p{margin:0}.locked p{color:var(--muted)}.final-panel{border:1px solid #777463;padding:30px 36px;background:#20231f}.final-header{display:flex;justify-content:space-between;align-items:center;gap:16px;flex-wrap:wrap}.final-panel .stamp{color:#ebbc95;border-color:#ad7851}.final-panel h2{font:700 26px var(--serif);margin:12px 0}.final-panel p{font-size:14px;color:#c7c6b8}.final-panel label{display:block;font-size:14px;margin-bottom:12px}.final-panel .digit{width:180px;background:#121510;border-color:#858271;color:var(--paper);letter-spacing:.35em}.final-panel .verify-button{background:#dbb489;color:#24201b}.final-panel .verify-button:hover{background:#ebcba5}.final-panel .feedback{color:#efba99}.final-panel .feedback.correct{color:#cce0b7}.preparation-screen{min-height:100vh;min-height:100svh;display:flex;justify-content:center;align-items:center;padding:32px;text-align:center}.preparation-screen h1{margin:0;font:700 clamp(22px,3vw,36px)/1.8 var(--serif);color:var(--paper)}.footer{border-top:1px solid #43453f;padding:24px 48px;max-width:1440px;margin:auto;display:flex;justify-content:space-between;gap:15px;color:#b0b0a2;font-size:12px}@media(min-width:1200px){.layout{gap:64px;grid-template-columns:290px minmax(0,1fr)}}@media(max-width:900px){.masthead{padding:20px 24px}.layout{padding:28px 24px;grid-template-columns:220px minmax(0,1fr);gap:24px}.document{padding:28px}.document h2{font-size:27px}.testimonies{grid-template-columns:1fr}.footer{padding:22px 24px}}@media(max-width:680px){.masthead{padding:18px 20px}.brand-name{font-size:16px}.mast-meta{display:none}.layout{display:block;padding:24px 16px 36px}.sidebar{position:static;padding:0 5px 25px}.sidebar h1{font-size:30px;margin:10px 0}.intro{margin:12px 0 20px}.nav{grid-template-columns:1fr 1fr;gap:0 16px}.nav a{padding:11px 0;grid-template-columns:24px 1fr;column-gap:5px}.nav-title{font-size:14px}.progress{margin-top:20px}.side-note{display:none}.document{padding:25px 22px;margin-bottom:20px}.document h2{font-size:26px}.doc-top{letter-spacing:0;flex-wrap:wrap}.evidence{padding:16px}.testimonies{grid-template-columns:1fr}.final-panel{padding:25px 22px}.final-panel .digit{width:160px}.verify-button{padding:12px 17px}.footer{padding:22px 20px;flex-direction:column;gap:4px}th,td{padding:10px 9px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}