*{box-sizing:border-box;margin:0;padding:0}body{color:#1a202c;background:#f7f8fa;height:100dvh;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif;overflow:hidden}.login-screen{text-align:center;color:#fff;background:linear-gradient(135deg,#667eea 0%,#4299e1 100%);flex-direction:column;justify-content:center;align-items:center;height:100dvh;display:flex}.login-screen h1{margin-bottom:4px;font-size:32px;font-weight:700}.login-subtitle{color:#fffc;margin-bottom:32px;font-size:16px}.login-logo{border-radius:22px;width:88px;height:88px;margin-bottom:20px;box-shadow:0 8px 24px #00000040}.btn-sign-in{color:#2b6cb0;cursor:pointer;background:#fff;border:none;border-radius:10px;padding:14px 40px;font-size:16px;font-weight:600;transition:transform .15s,box-shadow .15s;box-shadow:0 2px 12px #00000026}.btn-sign-in:hover{transform:translateY(-2px);box-shadow:0 6px 20px #0003}.app-layout{height:100dvh;display:flex}.main-area{background:#f7f8fa;flex-direction:column;flex:1;min-width:0;display:flex}.header{background:#fff;border-bottom:1px solid #edf0f4;flex-shrink:0;justify-content:space-between;align-items:center;padding:14px 20px;display:flex}.header-left{align-items:center;gap:10px;display:flex}.header-logo{border-radius:8px;width:30px;height:30px}.header h1{letter-spacing:-.01em;font-size:17px;font-weight:600}.company-badge{vertical-align:middle;letter-spacing:.02em;border-radius:5px;padding:3px 8px;font-size:11px;font-weight:700}.btn-menu{cursor:pointer;color:#a0aec0;background:0 0;border:none;border-radius:6px;padding:6px;transition:color .15s}.btn-menu:hover{color:#4a5568}.sidebar{color:#e2e8f0;background:#171923;flex-direction:column;flex-shrink:0;width:280px;transition:margin-left .25s;display:flex}.sidebar.collapsed{margin-left:-280px}.sidebar-overlay{display:none}.btn-collapse{color:#4a5568;cursor:pointer;background:0 0;border:none;border-radius:6px;padding:6px;transition:all .15s}.btn-collapse:hover{color:#e2e8f0;background:#2d3748}.sidebar-header{border-bottom:1px solid #ffffff0f;padding:14px}.btn-new-chat{color:#e2e8f0;cursor:pointer;background:#ffffff0f;border:1px solid #ffffff14;border-radius:8px;justify-content:center;align-items:center;gap:8px;width:100%;padding:10px 12px;font-size:13px;font-weight:500;transition:background .15s;display:flex}.btn-new-chat:hover{background:#ffffff1a}.chat-list{flex:1;padding:8px;overflow-y:auto}.chat-group-label{color:#4a5568;text-transform:uppercase;letter-spacing:.08em;padding:14px 10px 6px;font-size:10px;font-weight:600}.chat-item{cursor:pointer;border-radius:8px;justify-content:space-between;align-items:center;gap:8px;padding:9px 10px;transition:background .12s;display:flex}.chat-item:hover{background:#ffffff0f}.chat-item.active{background:#4299e126}.chat-title{text-overflow:ellipsis;white-space:nowrap;color:#cbd5e0;flex:1;font-size:13px;overflow:hidden}.chat-item.active .chat-title{color:#fff}.chat-actions{opacity:0;gap:2px;transition:opacity .15s;display:flex}.chat-item:hover .chat-actions{opacity:1}.chat-actions button{color:#4a5568;cursor:pointer;background:0 0;border:none;border-radius:4px;padding:4px}.chat-actions button:hover{color:#e2e8f0;background:#ffffff14}.rename-input{color:#e2e8f0;background:#ffffff0f;border:1px solid #ffffff1a;border-radius:5px;outline:none;width:100%;padding:5px 8px;font-size:13px}.no-chats{text-align:center;color:#4a5568;padding:32px 16px;font-size:13px}.sidebar-footer{border-top:1px solid #ffffff0f;padding:14px}.sidebar-user{color:#718096;text-overflow:ellipsis;white-space:nowrap;margin-bottom:8px;font-size:12px;display:block;overflow:hidden}.btn-sign-out{color:#718096;cursor:pointer;background:0 0;border:1px solid #ffffff0f;border-radius:6px;justify-content:center;align-items:center;gap:6px;width:100%;padding:8px;font-size:12px;transition:all .15s;display:flex}.btn-sign-out:hover{color:#e2e8f0;background:#ffffff0f}.chat-view{flex-direction:column;flex:1;min-height:0;display:flex;position:relative}.chat-view.drag-over:after{content:"Drop file here · 将文件拖放到这里";color:#4299e1;z-index:10;pointer-events:none;background:#4299e114;border:2px dashed #90cdf4;border-radius:12px;justify-content:center;align-items:center;margin:12px;font-size:16px;font-weight:600;display:flex;position:absolute;inset:0}.messages{flex-direction:column;flex:1;gap:16px;padding:24px 20px;display:flex;overflow-y:auto}.message{word-wrap:break-word;border-radius:18px;max-width:72%;padding:14px 18px;font-size:14px;line-height:1.6}.message-user{color:#fff;white-space:pre-wrap;background:#4299e1;border-bottom-right-radius:6px;align-self:flex-end}.message-bot{color:#2d3748;background:#fff;border-bottom-left-radius:6px;align-self:flex-start;box-shadow:0 1px 3px #0000000a,0 1px 2px #00000005}.msg-header{align-items:center;gap:6px;margin-bottom:8px;display:flex}.msg-avatar{border-radius:6px;width:22px;height:22px}.msg-name{color:#4299e1;letter-spacing:.01em;font-size:12px;font-weight:600}.msg-file{opacity:.75;margin-top:6px;font-size:12px}.msg-content{color:#2d3748;font-size:14px;line-height:1.65}.msg-content p{margin-bottom:8px}.msg-content p:last-child{margin-bottom:0}.msg-content strong{color:#1a202c;font-weight:600}.msg-content em{font-style:italic}.msg-content ul,.msg-content ol{margin:6px 0 6px 20px}.msg-content li{margin-bottom:3px}.msg-content li::marker{color:#a0aec0}.msg-content code{color:#c53030;background:#edf2f7;border-radius:4px;padding:2px 5px;font-family:SF Mono,Fira Code,Consolas,monospace;font-size:13px}.msg-content pre{color:#e2e8f0;background:#1a202c;border-radius:8px;margin:8px 0;padding:14px 16px;font-size:13px;line-height:1.5;overflow-x:auto}.msg-content pre code{color:inherit;font-size:inherit;background:0 0;padding:0}.msg-content table{border-collapse:collapse;width:100%;margin:8px 0;font-size:13px}.msg-content th{text-align:left;color:#4a5568;background:#f7fafc;border-bottom:2px solid #e2e8f0;padding:8px 10px;font-size:12px;font-weight:600}.msg-content td{border-bottom:1px solid #f0f0f0;padding:7px 10px}.msg-content tr:hover td{background:#f7fafc}.msg-content h1,.msg-content h2,.msg-content h3{color:#1a202c;margin:12px 0 6px;font-weight:600}.msg-content h1{font-size:18px}.msg-content h2{font-size:16px}.msg-content h3{font-size:15px}.msg-content blockquote{color:#4a5568;background:#f7fafc;border-left:3px solid #4299e1;border-radius:0 6px 6px 0;margin:8px 0;padding:4px 12px}.msg-content hr{border:none;border-top:1px solid #e2e8f0;margin:12px 0}.msg-content a{color:#4299e1;text-decoration:none}.msg-content a:hover{text-decoration:underline}.typing-dots{gap:5px;padding:4px 0;display:flex}.typing-dots span{background:#cbd5e0;border-radius:50%;width:8px;height:8px;animation:1.4s ease-in-out infinite bounce}.typing-dots span:nth-child(2){animation-delay:.2s}.typing-dots span:nth-child(3){animation-delay:.4s}@keyframes bounce{0%,80%,to{opacity:.5;transform:scale(.8)}40%{opacity:1;transform:scale(1.2)}}.welcome,.empty-state{text-align:center;color:#a0aec0;flex-direction:column;flex:1;justify-content:center;align-items:center;padding:20px;display:flex}.welcome img,.empty-state img{opacity:.6;border-radius:16px;width:64px;height:64px;margin-bottom:16px}.welcome p,.empty-state p{margin-bottom:8px;font-size:16px;line-height:1.5}.suggestions{flex-wrap:wrap;justify-content:center;gap:8px;max-width:500px;margin-top:12px;display:flex}.suggestion{color:#4a5568;cursor:pointer;background:#fff;border:1px solid #e2e8f0;border-radius:20px;padding:9px 18px;font-size:13px;transition:all .15s;box-shadow:0 1px 2px #00000008}.suggestion:hover{color:#4299e1;border-color:#4299e1;transform:translateY(-1px);box-shadow:0 2px 6px #4299e11f}.btn-primary{color:#fff;cursor:pointer;background:#4299e1;border:none;border-radius:10px;margin-top:12px;padding:12px 28px;font-size:14px;font-weight:600;transition:background .15s}.btn-primary:hover{background:#3182ce}.input-area{background:#fff;border-top:1px solid #edf0f4;flex-shrink:0;padding:14px 20px}.input-wrapper{max-width:800px;margin:0 auto}.input-row{align-items:flex-end;gap:8px;display:flex}.input-row textarea{resize:none;background:#f7f8fa;border:1px solid #e2e8f0;border-radius:14px;outline:none;flex:1;max-height:120px;padding:11px 16px;font-family:inherit;font-size:14px;line-height:1.45;transition:border-color .15s,box-shadow .15s,background .15s}.input-row textarea:focus{background:#fff;border-color:#4299e1;box-shadow:0 0 0 3px #4299e11a}.btn-icon{cursor:pointer;color:#a0aec0;background:0 0;border:1px solid #e2e8f0;border-radius:12px;flex-shrink:0;justify-content:center;align-items:center;width:42px;height:42px;transition:all .15s;display:flex}.btn-icon:hover{color:#4299e1;background:#4299e10a;border-color:#4299e1}.btn-icon.recording{color:#e53e3e;background:#e53e3e0a;border-color:#e53e3e;animation:1.5s infinite pulse-ring}@keyframes pulse-ring{0%{box-shadow:0 0 #e53e3e40}70%{box-shadow:0 0 0 8px #e53e3e00}to{box-shadow:0 0 #e53e3e00}}.btn-send{color:#fff;cursor:pointer;background:#4299e1;border:none;border-radius:12px;flex-shrink:0;justify-content:center;align-items:center;width:42px;height:42px;transition:background .15s,transform .1s;display:flex}.btn-send:hover{background:#3182ce;transform:scale(1.04)}.btn-send:disabled{cursor:not-allowed;background:#cbd5e0;transform:none}.file-preview{padding:8px 0}.file-chip{color:#2b6cb0;background:#ebf8ff;border-radius:8px;align-items:center;gap:6px;padding:5px 12px;font-size:13px;display:inline-flex}.file-name{text-overflow:ellipsis;white-space:nowrap;max-width:200px;overflow:hidden}.file-size{color:#90cdf4;font-size:11px}.file-remove{cursor:pointer;color:#90cdf4;font-size:16px;line-height:1}.file-remove:hover{color:#e53e3e}.recording-bar{color:#e53e3e;align-items:center;gap:10px;padding:8px 0;font-size:13px;display:flex}.recording-dot{background:#e53e3e;border-radius:50%;width:8px;height:8px;animation:1s infinite blink}@keyframes blink{0%,to{opacity:1}50%{opacity:.2}}.rec-time{color:#718096;font-family:SF Mono,monospace}.rec-cancel{color:#718096;cursor:pointer;font-size:12px;text-decoration:underline}.rec-cancel:hover{color:#e53e3e}@media (width<=768px){.sidebar{z-index:100;width:280px;transition:left .25s;position:fixed;top:0;bottom:0;left:0}.sidebar.collapsed{margin-left:0;left:-280px}.sidebar-overlay{z-index:99;background:#00000080;position:fixed;inset:0}.messages{padding:16px 12px}.message{max-width:88%;padding:10px 14px}.header{padding:10px 12px}.header h1{font-size:15px}.suggestion{padding:7px 14px;font-size:12px}.input-area{padding:10px 12px}}