*{box-sizing:border-box}body{margin:0;font-family:system-ui,-apple-system,sans-serif;background:#f7f7fa;color:#1a1a1a}header.topbar{background:#4f46e5;color:#fff;padding:12px 20px;font-weight:600;font-size:18px}main{max-width:1000px;margin:0 auto;padding:24px 20px}nav.subnav{display:flex;gap:16px;margin-bottom:20px;border-bottom:1px solid #ddd;padding-bottom:8px}nav.subnav a{color:#4f46e5;text-decoration:none;font-size:14px}nav.subnav a.active{font-weight:700}table{width:100%;border-collapse:collapse;background:#fff}th,td{text-align:left;padding:8px 10px;border-bottom:1px solid #eee;font-size:14px}th{background:#f0f0f5}button{background:#4f46e5;color:#fff;border:none;padding:6px 14px;border-radius:6px;cursor:pointer;font-size:14px}button:hover{opacity:.9}button.secondary{background:#e5e5ea;color:#333}input,textarea{padding:6px 8px;border:1px solid #ccc;border-radius:4px;font-size:14px}.card{background:#fff;border-radius:8px;padding:16px;margin-bottom:16px}.error{color:#b91c1c;font-size:14px}.muted{color:#666;font-size:13px}.stat-row{display:flex;gap:24px;flex-wrap:wrap}.stat{background:#fff;border-radius:8px;padding:16px 20px;min-width:140px}.stat .value{font-size:28px;font-weight:700;color:#4f46e5}.stat .label{font-size:13px;color:#666}.msg{padding:8px 12px;border-radius:8px;margin-bottom:8px;max-width:75%}.msg.user{background:#4f46e5;color:#fff;margin-left:auto}.msg.assistant{background:#eee}