.chat-app{max-width:800px;margin:0 auto;height:100vh;display:flex;flex-direction:column;background:#f5f5f5;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif}.chat-header{background:#fff;padding:20px;text-align:center;box-shadow:0 2px 4px #0000001a}.chat-header h1{margin:0;color:#333;font-size:24px}.chat-header p{margin:5px 0 0;color:#666;font-size:14px}.chat-messages{flex:1;padding:20px;overflow-y:auto;background:#fff;margin:10px;border-radius:10px;box-shadow:0 2px 4px #0000001a}.empty-state{text-align:center;color:#999;padding:40px 20px}.message{display:flex;margin-bottom:16px}.message.user{justify-content:flex-end}.message.bot{justify-content:flex-start}.message-bubble{max-width:70%;padding:12px 16px;border-radius:18px;position:relative}.message.user .message-bubble{background:#007bff;color:#fff;border-bottom-right-radius:4px}.message.bot .message-bubble{background:#e9ecef;color:#333;border-bottom-left-radius:4px}.message-content{word-wrap:break-word;white-space:pre-wrap}.message-time{font-size:11px;opacity:.7;margin-top:4px;text-align:right}.uploading-indicator{color:#666;font-style:italic}.chat-input-area{background:#fff;padding:20px;box-shadow:0 -2px 4px #0000001a}.file-upload-form{margin-bottom:15px}.upload-section{display:flex;gap:10px;align-items:center}#file-input{display:none}.file-label{padding:8px 16px;background:#6c757d;color:#fff;border-radius:20px;cursor:pointer;font-size:14px;transition:background .2s}.file-label:hover{background:#5a6268}.upload-btn{padding:8px 16px;background:#28a745;color:#fff;border:none;border-radius:20px;cursor:pointer;font-size:14px;transition:background .2s}.upload-btn:hover:not(:disabled){background:#218838}.upload-btn:disabled{background:#ccc;cursor:not-allowed}.text-input-section{display:flex;gap:10px;align-items:flex-end}.text-input-section textarea{flex:1;padding:12px;border:1px solid #ddd;border-radius:20px;resize:none;font-family:inherit;font-size:14px;outline:none;transition:border-color .2s}.text-input-section textarea:focus{border-color:#007bff}.text-input-section textarea:disabled{background:#f8f9fa;cursor:not-allowed}.send-btn{padding:12px 24px;background:#007bff;color:#fff;border:none;border-radius:20px;cursor:pointer;font-size:14px;transition:background .2s}.send-btn:hover:not(:disabled){background:#0056b3}.send-btn:disabled{background:#ccc;cursor:not-allowed}.chat-messages::-webkit-scrollbar{width:6px}.chat-messages::-webkit-scrollbar-track{background:#f1f1f1;border-radius:3px}.chat-messages::-webkit-scrollbar-thumb{background:#c1c1c1;border-radius:3px}.chat-messages::-webkit-scrollbar-thumb:hover{background:#a8a8a8}*{box-sizing:border-box;padding:0;margin:0}body{background-color:#000;color:#f5f5f5}h2{margin-top:50px;text-align:center;text-transform:uppercase}