.chatroom{max-width:800px;margin:2rem auto;background-color:#fff;padding:1.5rem;border-radius:8px;border:1px solid #e0e0e0;box-shadow:0 2px 4px #0000001a}.messages{max-height:400px;overflow-y:auto;margin-bottom:1rem;color:#333}.message{margin-bottom:1rem}.message-user{font-weight:700;color:#007bff}.message-timestamp{font-size:.8em;color:#888;display:block;text-align:right}textarea{width:100%;padding:.5rem;margin-bottom:1rem;border:1px solid #ccc;border-radius:4px;resize:vertical}button{padding:.5rem 1rem;margin-left:.5rem;border:none;background-color:#007bff;color:#fff;border-radius:4px;cursor:pointer;transition:background-color .3s ease}button:focus,textarea:focus{border-color:#007bff;outline:none}#root{max-width:800px;margin:0 auto;padding:2rem;text-align:center;background-color:#f9f9f9;color:#333;font-family:Arial,sans-serif}h1{font-size:2rem;margin-bottom:1rem}.card{padding:1.5rem;border:1px solid #e0e0e0;border-radius:8px;background-color:#fff;box-shadow:0 2px 4px #0000001a}input[type=text]{padding:.5rem;margin-right:.5rem;border:1px solid #ccc;border-radius:4px;width:calc(100% - 2rem)}button{padding:.5rem 1rem;border:none;background-color:#007bff;color:#fff;border-radius:4px;cursor:pointer;transition:background-color .3s ease}button:hover{background-color:#0056b3}input[type=text]:focus{border-color:#007bff;outline:none}.navigation-bar{display:flex;justify-content:space-between;padding:1rem 2rem;background-color:#fff;border-bottom:1px solid #e0e0e0;box-shadow:0 2px 4px #0000001a}.navigation-bar button{padding:.5rem 1rem;border:none;background-color:#007bff;color:#fff;border-radius:4px;cursor:pointer;transition:background-color .3s ease}.navigation-bar button:hover{background-color:#0056b3}body{margin:0;padding:0;font-family:Arial,sans-serif;background-color:#f5f5f5;color:#333}*{box-sizing:border-box}