body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f0f0f0;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

#username-section {
    text-align: center;
    padding: 20px;
}

#chat-section {
    background: white;
    border-radius: 5px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

#messages {
    height: 400px;
    overflow-y: auto;
    padding: 20px;
}

.message {
    margin: 10px 0;
    padding: 10px;
    border-radius: 3px;
    background: #f9f9f9;
}

.message .username {
    font-weight: bold;
    margin-right: 10px;
}

.message .timestamp {
    color: #666;
    font-size: 0.8em;
}

#message-form {
    display: flex;
    padding: 10px;
}

#message-input {
    flex-grow: 1;
    padding: 5px;
    margin-right: 10px;
}

button {
    padding: 5px 15px;
    background: #007bff;
    color: white;
    border: none;
    border-radius: 3px;
    cursor: pointer;
}

button:hover {
    background: #0056b3;
}