:root{--primary: #2d6a4f;--primary-light: #40916c;--primary-dark: #1b4332;--accent: #b7e4c7;--accent-warm: #f4a261;--bg: #fefae0;--bg-card: #ffffff;--text: #2c2c2c;--text-light: #6c757d;--border: #d8d8d8;--shadow: 0 2px 12px rgba(0,0,0,.08);--radius: 12px}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Noto Sans SC,sans-serif;background:var(--bg);color:var(--text);min-height:100vh}.app-layout{display:flex;min-height:100vh}.sidebar{width:220px;background:linear-gradient(180deg,var(--primary-dark) 0%,var(--primary) 100%);color:#fff;display:flex;flex-direction:column;position:fixed;top:0;left:0;bottom:0;z-index:100}.sidebar-header{padding:24px 20px 20px;display:flex;align-items:center;gap:10px;border-bottom:1px solid rgba(255,255,255,.15)}.sidebar-logo{font-size:28px}.sidebar-title{font-size:16px;font-weight:600;letter-spacing:1px}.sidebar-nav{flex:1;padding:16px 12px;display:flex;flex-direction:column;gap:4px}.nav-item{display:flex;align-items:center;gap:10px;padding:10px 14px;border-radius:8px;color:#fffc;text-decoration:none;font-size:14px;transition:all .2s}.nav-item:hover{background:#ffffff1f;color:#fff}.nav-active{background:#ffffff2e;color:#fff;font-weight:600}.nav-icon{font-size:18px;width:24px;text-align:center}.nav-label{white-space:nowrap}.sidebar-footer{padding:16px 20px;border-top:1px solid rgba(255,255,255,.15);font-size:12px;color:#ffffff80;line-height:1.6}.sidebar-version{font-size:11px;opacity:.7}.main-content{margin-left:220px;flex:1;padding:32px 40px;min-height:100vh}.home-hero{background:linear-gradient(135deg,var(--primary) 0%,var(--primary-light) 100%);border-radius:var(--radius);padding:48px 40px;color:#fff;margin-bottom:32px}.home-hero h2{font-size:32px;margin-bottom:12px}.home-hero p{font-size:16px;opacity:.9;line-height:1.7}.feature-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:20px}.feature-card{background:var(--bg-card);border-radius:var(--radius);padding:28px 24px;box-shadow:var(--shadow);cursor:pointer;text-decoration:none;color:var(--text);transition:transform .2s,box-shadow .2s;border:1px solid var(--border)}.feature-card:hover{transform:translateY(-4px);box-shadow:0 8px 24px #0000001f}.feature-card-icon{font-size:36px;margin-bottom:14px}.feature-card h3{font-size:17px;margin-bottom:8px;color:var(--primary-dark)}.feature-card p{font-size:13px;color:var(--text-light);line-height:1.6}.page-header{margin-bottom:28px}.page-header h2{font-size:24px;color:var(--primary-dark);margin-bottom:6px}.page-header p{font-size:14px;color:var(--text-light)}.search-bar{display:flex;gap:10px;margin-bottom:24px}.search-bar input{flex:1;padding:10px 16px;border:1px solid var(--border);border-radius:8px;font-size:14px;outline:none;transition:border-color .2s}.search-bar input:focus{border-color:var(--primary-light)}.search-bar button{padding:10px 20px;background:var(--primary);color:#fff;border:none;border-radius:8px;cursor:pointer;font-size:14px;transition:background .2s}.search-bar button:hover{background:var(--primary-dark)}.lit-card{background:var(--bg-card);border-radius:var(--radius);padding:20px 24px;margin-bottom:14px;box-shadow:var(--shadow);border-left:4px solid var(--primary-light)}.lit-card h4{font-size:16px;color:var(--primary-dark);margin-bottom:6px}.lit-card .lit-meta{font-size:12px;color:var(--text-light);margin-bottom:8px}.lit-card .lit-summary{font-size:14px;line-height:1.7;color:var(--text)}.lit-tag{display:inline-block;padding:2px 10px;background:#e8f5e9;color:var(--primary);border-radius:20px;font-size:12px;margin-right:6px;margin-top:8px}.graph-container{background:var(--bg-card);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow);min-height:500px;position:relative;overflow:hidden}.graph-legend{display:flex;gap:16px;margin-bottom:20px;flex-wrap:wrap}.legend-item{display:flex;align-items:center;gap:6px;font-size:13px;color:var(--text-light)}.legend-dot{width:12px;height:12px;border-radius:50%}.graph-node{position:absolute;padding:8px 16px;border-radius:20px;font-size:13px;font-weight:500;cursor:pointer;transition:transform .2s,box-shadow .2s;z-index:10;text-align:center;max-width:120px}.graph-node:hover{transform:scale(1.08);z-index:20}.graph-edge{position:absolute;z-index:1;pointer-events:none}.graph-tooltip{position:fixed;background:#fff;border-radius:8px;padding:12px 16px;box-shadow:0 4px 20px #00000026;font-size:13px;line-height:1.6;max-width:260px;z-index:1000;display:none}.qa-container{display:flex;flex-direction:column;height:calc(100vh - 180px);max-width:800px}.qa-messages{flex:1;overflow-y:auto;padding:16px 0;display:flex;flex-direction:column;gap:16px}.qa-bubble{max-width:80%;padding:12px 18px;border-radius:16px;font-size:14px;line-height:1.7}.qa-bubble.user{align-self:flex-end;background:var(--primary);color:#fff;border-bottom-right-radius:4px}.qa-bubble.ai{align-self:flex-start;background:var(--bg-card);border:1px solid var(--border);border-bottom-left-radius:4px}.qa-input-bar{display:flex;gap:10px;padding:16px 0;border-top:1px solid var(--border)}.qa-input-bar input{flex:1;padding:10px 16px;border:1px solid var(--border);border-radius:8px;font-size:14px;outline:none}.qa-input-bar input:focus{border-color:var(--primary-light)}.qa-input-bar button{padding:10px 24px;background:var(--primary);color:#fff;border:none;border-radius:8px;cursor:pointer;font-size:14px}.qa-input-bar button:hover{background:var(--primary-dark)}.qa-input-bar button:disabled{opacity:.5;cursor:not-allowed}.qa-quick-btns{display:flex;gap:8px;flex-wrap:wrap;padding:8px 0}.qa-quick-btn{padding:6px 14px;background:#e8f5e9;color:var(--primary);border:none;border-radius:20px;cursor:pointer;font-size:13px;transition:background .2s}.qa-quick-btn:hover{background:#c8e6c9}.course-form{background:var(--bg-card);border-radius:var(--radius);padding:28px;box-shadow:var(--shadow);max-width:700px;margin-bottom:24px}.form-group{margin-bottom:20px}.form-group label{display:block;font-size:14px;font-weight:600;color:var(--primary-dark);margin-bottom:8px}.form-group input,.form-group textarea,.form-group select{width:100%;padding:10px 14px;border:1px solid var(--border);border-radius:8px;font-size:14px;outline:none;font-family:inherit}.form-group input:focus,.form-group textarea:focus,.form-group select:focus{border-color:var(--primary-light)}.form-group textarea{min-height:100px;resize:vertical}.form-row{display:grid;grid-template-columns:1fr 1fr;gap:16px}.btn-primary{padding:12px 32px;background:var(--primary);color:#fff;border:none;border-radius:8px;cursor:pointer;font-size:15px;font-weight:600;transition:background .2s}.btn-primary:hover{background:var(--primary-dark)}.btn-primary:disabled{opacity:.5}.course-result{background:var(--bg-card);border-radius:var(--radius);padding:28px;box-shadow:var(--shadow);animation:fadeIn .4s ease}.course-result h3{font-size:20px;color:var(--primary-dark);margin-bottom:16px;padding-bottom:12px;border-bottom:2px solid var(--accent)}.course-section{margin-bottom:20px}.course-section h4{font-size:15px;color:var(--primary);margin-bottom:8px}.course-section p,.course-section li{font-size:14px;line-height:1.8;color:var(--text)}.course-section ul{padding-left:20px}.quiz-container{max-width:700px}.quiz-start{background:var(--bg-card);border-radius:var(--radius);padding:40px;box-shadow:var(--shadow);text-align:center}.quiz-start h3{font-size:22px;color:var(--primary-dark);margin-bottom:12px}.quiz-start p{font-size:14px;color:var(--text-light);margin-bottom:24px}.quiz-progress{display:flex;align-items:center;gap:12px;margin-bottom:20px}.quiz-progress-bar{flex:1;height:8px;background:#e0e0e0;border-radius:4px;overflow:hidden}.quiz-progress-fill{height:100%;background:var(--primary);border-radius:4px;transition:width .4s ease}.quiz-progress-text{font-size:13px;color:var(--text-light);white-space:nowrap}.quiz-card{background:var(--bg-card);border-radius:var(--radius);padding:28px;box-shadow:var(--shadow);margin-bottom:20px}.quiz-question{font-size:17px;font-weight:600;margin-bottom:20px;line-height:1.6}.quiz-options{display:flex;flex-direction:column;gap:10px}.quiz-option{padding:12px 18px;border:2px solid var(--border);border-radius:10px;cursor:pointer;font-size:14px;transition:all .2s;background:#fff}.quiz-option:hover{border-color:var(--primary-light);background:#f0faf4}.quiz-option.selected{border-color:var(--primary);background:#e8f5e9}.quiz-option.correct{border-color:#4caf50;background:#e8f5e9}.quiz-option.wrong{border-color:#ef5350;background:#ffebee}.quiz-feedback{margin-top:16px;padding:14px 18px;border-radius:10px;font-size:14px;line-height:1.7;animation:fadeIn .3s ease}.quiz-feedback.correct{background:#e8f5e9;color:#2e7d32}.quiz-feedback.wrong{background:#ffebee;color:#c62828}.quiz-result{background:var(--bg-card);border-radius:var(--radius);padding:40px;box-shadow:var(--shadow);text-align:center}.quiz-result h3{font-size:24px;margin-bottom:12px}.quiz-result .score{font-size:48px;font-weight:700;color:var(--primary);margin:16px 0}.quiz-result .score span{font-size:20px;color:var(--text-light)}@keyframes fadeIn{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}@media (max-width: 768px){.sidebar{width:60px}.sidebar-title,.nav-label,.sidebar-footer{display:none}.main-content{margin-left:60px;padding:20px}.home-hero{padding:28px 20px}.home-hero h2{font-size:22px}.form-row{grid-template-columns:1fr}}