.topic-intro{border:1px solid #dbe6f5;background:#ecf3fd;border-radius:12px;padding:20px 24px;margin-bottom:24px}.topic-tag{font-size:10px;letter-spacing:1.5px;color:#426da8;font-weight:700}.topic-intro p{font-size:14px;line-height:1.8;color:#526a89;max-width:850px;margin:8px 0 0}.topic-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px;align-items:start}.topic-card{padding:25px;min-width:0}.topic-card-top{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px}.topic-number{font-size:13px;font-weight:700;color:#4d7aba;padding:9px 11px;background:#edf3fc;border-radius:8px}.topic-status{font-size:11px;background:#f0f3f7;color:#718197;border-radius:20px;padding:6px 11px}.topic-status.started{color:#277159;background:#e5f4ee}.topic-card h2{font-size:21px;letter-spacing:-.4px;line-height:1.4;margin:0 0 10px}.topic-card>p{font-size:14px;line-height:1.8;color:#64758c}.topic-card details{border-top:1px solid #e8edf4;padding:15px 0;margin-top:18px}.topic-card summary{cursor:pointer;font-size:13px;color:#375d90}.topic-card ul{padding-left:20px;margin-bottom:0}.topic-card li{font-size:13px;line-height:1.8;margin:7px 0;color:#49627e}.topic-card li small{color:#347b63}.topic-book{background:#f7f9fc;border-radius:8px;padding:14px;margin-top:6px}.topic-book>span{font-size:9px;letter-spacing:1.3px;color:#8090a5;font-weight:700}.topic-book p{font-size:12px;line-height:1.7;color:#7b889b;margin:7px 0 0}.topic-card p.topic-placeholder{font-size:12px;color:#7a899b;margin-bottom:0}.topic-card p.topic-progress{font-size:12px;color:#36775f}.topic-card .primary{margin-top:3px}.topic-bottom{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-top:24px;padding:20px 24px;background:#fff;border:1px solid #e3e9f1;border-radius:12px}.topic-bottom p{font-size:13px;line-height:1.8;color:#5f7390;max-width:630px;margin:0}.topic-bottom button{flex-shrink:0}@media(max-width:1000px){.topic-grid{grid-template-columns:1fr}.topic-bottom{align-items:flex-start;flex-direction:column}}@media(max-height:850px) and (min-width:801px){.sidebar .side-note{display:none}.sidebar{overflow-y:auto}.sidebar .profile{margin-top:24px}}