@import"https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Noto+Serif+SC:wght@400;700&display=swap";:root{--primary: #171717;--secondary: #404040;--accent: #d4af37;--bg-page: #fdfdfd;--bg-panel: #ffffff;--border: #eeeeee;--text-main: #171717;--text-muted: #666666;--radius: 8px;--shadow-sm: 0 1px 2px 0 rgb(0 0 0 / .05);--shadow-md: 0 4px 6px -1px rgb(0 0 0 / .1)}*{box-sizing:border-box}html,body{margin:0;padding:0;font-family:Inter,PingFang SC,Hiragino Sans GB,Microsoft YaHei,sans-serif;background:var(--bg-page);color:var(--text-main);-webkit-font-smoothing:antialiased}.page{min-height:100vh;display:flex;flex-direction:column}.header{padding:16px 40px;border-bottom:1px solid var(--border);background:#ffffffe6;-webkit-backdrop-filter:blur(12px);backdrop-filter:blur(12px);position:sticky;top:0;z-index:50;display:flex;justify-content:space-between;align-items:center}.title{font-size:18px;font-weight:700;letter-spacing:-.02em}.meta{font-size:12px;color:var(--text-muted);font-weight:500}.main{flex:1;display:grid;grid-template-columns:280px 1fr 400px;gap:0;padding:0;max-width:100vw}.left{border-right:1px solid var(--border);background:var(--bg-panel);height:calc(100vh - 65px);position:sticky;top:65px;padding:24px;overflow-y:auto}.panelTitle{font-weight:600;font-size:11px;text-transform:uppercase;letter-spacing:.1em;color:var(--text-muted);margin-bottom:20px}.chapterList{display:flex;flex-direction:column;gap:4px}.chapterItem{text-align:left;border:none;background:transparent;color:var(--text-muted);border-radius:var(--radius);padding:12px 14px;cursor:pointer;font-size:14px;font-weight:500;transition:all .2s ease;line-height:1.4}.chapterItem:hover{background:#f5f5f5;color:var(--text-main)}.chapterItem.active{background:#171717;color:#fff}.chapterTitle{font-weight:600;margin-bottom:4px}.chapterSummary{font-size:12px;opacity:.8;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.readerArea{padding:60px 80px;background:var(--bg-page);height:calc(100vh - 65px);overflow-y:auto}.readerContent{max-width:720px;margin:0 auto}.contentTitle{font-size:36px;font-weight:700;margin-bottom:48px;font-family:Inter,sans-serif;letter-spacing:-.04em;line-height:1.2}.bookText{font-family:"Noto Serif SC",serif;font-size:19px;line-height:2;color:#1a1a1a;white-space:pre-wrap;word-break:break-word}.right{border-left:1px solid var(--border);background:var(--bg-panel);height:calc(100vh - 65px);position:sticky;top:65px;display:flex;flex-direction:column}.tabs{display:flex;padding:12px 16px 0;border-bottom:1px solid var(--border);gap:8px}.tab{padding:10px 16px;font-size:13px;font-weight:600;cursor:pointer;border-radius:6px 6px 0 0;color:var(--text-muted);transition:all .2s;border:1px solid transparent;border-bottom:none;margin-bottom:-1px}.tab:hover{color:var(--text-main)}.tab.active{background:var(--bg-panel);color:var(--text-main);border-color:var(--border)}.tabContent{flex:1;padding:24px;overflow-y:auto}.summaryBox{background:#f9f9f9;border-radius:12px;padding:20px;margin-bottom:24px;border:1px solid var(--border)}.summaryMeta{font-size:11px;text-transform:uppercase;letter-spacing:.05em;color:var(--text-muted);margin-bottom:10px;font-weight:700}.summaryText{font-size:14px;line-height:1.7;color:var(--secondary)}.summaryText p{margin:0 0 12px}.summaryText p:last-child{margin-bottom:0}.summaryText strong{font-weight:700;color:var(--primary)}.chatPanel{display:flex;flex-direction:column;height:100%}.chatList{flex:1;display:flex;flex-direction:column;gap:20px;overflow-y:auto;padding-bottom:24px}.chatMsg{display:flex;flex-direction:column;gap:6px}.chatRole{font-size:11px;font-weight:700;text-transform:uppercase;letter-spacing:.05em;color:var(--text-muted);margin-left:4px}.chatBubble{padding:12px 16px;border-radius:12px;font-size:14px;line-height:1.6;max-width:95%;border:1px solid var(--border)}.chatText{line-height:1.6;font-size:14px;color:inherit}.chatText p{margin:0 0 12px}.chatText p:last-child{margin-bottom:0}.chatText ul,.chatText ol{margin:0 0 12px;padding-left:20px}.chatText li{margin-bottom:4px}.chatText strong{font-weight:700;color:var(--primary)}.chatMsg.user .chatText strong{color:#fff}.chatText h3{font-size:15px;font-weight:700;margin:16px 0 8px;color:var(--primary)}.chatMsg.user .chatText h3{color:#fff}.chatMsg.user{align-items:flex-end}.chatMsg.user .chatBubble{background:#171717;color:#fff;border-color:#171717}.chatMsg.assistant{align-items:flex-start}.chatMsg.assistant .chatBubble{background:#fff;color:var(--text-main);box-shadow:var(--shadow-sm)}.chatInputRow{display:flex;gap:10px;padding-top:16px;border-top:1px solid var(--border)}.chatInput{flex:1;padding:12px 16px;border-radius:var(--radius);border:1px solid var(--border);font-family:inherit;font-size:14px;outline:none;transition:all .2s;background:#f9f9f9}.chatInput:focus{background:#fff;border-color:var(--primary);box-shadow:0 0 0 2px #0000000d}.primaryBtn{background:#171717;color:#fff;border:none;padding:0 20px;border-radius:var(--radius);font-weight:600;font-size:13px;cursor:pointer;transition:opacity .2s}.primaryBtn:hover{opacity:.9}.ghostBtn{background:transparent;color:var(--text-main);border:1px solid var(--border);padding:8px 16px;border-radius:var(--radius);font-weight:600;font-size:12px;cursor:pointer}.ghostBtn:hover{background:#f5f5f5}.citations{margin-top:12px;display:flex;flex-direction:column;gap:8px}.citationsTitle{font-size:11px;font-weight:700;color:var(--text-muted);text-transform:uppercase}.citation{padding:10px;border-radius:8px;background:#fcfcfc;border:1px solid var(--border)}.citationMeta{font-size:10px;color:var(--text-muted);margin-bottom:4px}.citationText{font-size:12px;line-height:1.5;color:var(--secondary)}.quizItem{background:#fff;border:1px solid var(--border);border-radius:12px;padding:24px;margin-bottom:20px}.quizQ{font-size:15px;font-weight:700;margin-bottom:16px;line-height:1.5}.quizOptions{display:flex;flex-direction:column;gap:8px}.quizOption{display:block;width:100%;text-align:left;padding:12px 16px;border:1px solid var(--border);border-radius:8px;background:#fff;cursor:pointer;font-size:14px;transition:all .2s}.quizOption:hover{background:#f9f9f9;border-color:#171717}.quizAns{margin-top:20px;padding:16px;background:#f9f9f9;border-radius:8px;font-size:13px;line-height:1.6}.ansBtn{margin-top:12px;background:transparent;border:1px solid var(--border);color:var(--text-main);padding:6px 14px;border-radius:6px;font-size:12px;font-weight:600;cursor:pointer}.row{display:flex;align-items:center;gap:12px;margin-bottom:20px}.radio{display:flex;align-items:center;gap:6px;font-size:13px;font-weight:500;cursor:pointer}.hint{font-size:12px;color:var(--text-muted);text-align:center;padding:40px 20px}@media (max-width: 1200px){.main{grid-template-columns:240px 1fr}.right{display:none}}