:root{--primary: #8b5a2b;--primary-light: #c49a6c;--bg: #f7f3ee;--card: #ffffff;--text: #2c2420;--muted: #8a7d72;--border: #e4d9cc;--danger: #c0392b}*{box-sizing:border-box;margin:0;padding:0}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,PingFang SC,Microsoft YaHei,sans-serif;background:var(--bg);color:var(--text);line-height:1.6}a{color:var(--primary);text-decoration:none}button{cursor:pointer;font-family:inherit}.app-shell{min-height:100vh;display:flex;flex-direction:column}.topbar{background:var(--primary);color:#fff;padding:12px 20px;display:flex;align-items:center;justify-content:space-between;box-shadow:0 1px 4px #00000014}.topbar .brand{font-size:18px;font-weight:600}.topbar nav{display:flex;gap:16px;align-items:center}.topbar nav a{color:#fff;opacity:.9}.topbar nav a:hover{opacity:1}.topbar nav button{background:#ffffff26;color:#fff;border:none;padding:6px 12px;border-radius:6px}.container{max-width:840px;margin:0 auto;padding:20px;width:100%}.card{background:var(--card);border:1px solid var(--border);border-radius:12px;padding:20px;margin-bottom:16px}.btn{background:var(--primary);color:#fff;border:none;padding:10px 18px;border-radius:8px;font-size:14px}.btn:disabled{opacity:.5}.btn-secondary{background:var(--primary-light)}input,textarea,select{width:100%;padding:10px 12px;border:1px solid var(--border);border-radius:8px;font-size:14px;font-family:inherit}input:focus,textarea:focus{outline:2px solid var(--primary-light)}.field{margin-bottom:14px}.field label{display:block;margin-bottom:6px;font-size:14px;color:var(--muted)}.hero{text-align:center;padding:40px 20px}.hero h1{color:var(--primary);font-size:26px;margin-bottom:10px}.hero p{color:var(--muted);margin-bottom:24px}.chat-box{display:flex;flex-direction:column;gap:12px;max-height:60vh;overflow-y:auto;padding:4px}.msg{max-width:80%;padding:10px 14px;border-radius:12px;font-size:14px;white-space:pre-wrap}.msg.user{align-self:flex-end;background:var(--primary);color:#fff}.msg.assistant{align-self:flex-start;background:#f0e9df}.msg.system{align-self:center;background:#fdf3e7;color:var(--danger);border:1px dashed var(--danger);max-width:100%}.chat-input{display:flex;gap:10px;margin-top:16px}.chat-input input{flex:1}.disclaimer{background:#fdf6ec;border:1px solid #f3d19e;color:#94623f;padding:10px 14px;border-radius:8px;font-size:13px;margin-bottom:16px}.report-section h3{color:var(--primary);margin:16px 0 8px}.tag{display:inline-block;background:var(--primary-light);color:#fff;padding:2px 10px;border-radius:10px;font-size:12px;margin:2px}.loading{text-align:center;padding:40px;color:var(--muted)}ul.tight{padding-left:18px}ul.tight li{margin-bottom:4px}.session-list a{display:block;padding:12px;border-bottom:1px solid var(--border)}.session-list a:hover{background:var(--bg)}