:root {
    --primary-color: #007bff;
    --secondary-color: #f8f9fa;
    --background-color: #e9ecef;
    --card-background: #fff;
    --text-color: #212529;
}

body {
    font-family: 'Roboto', sans-serif;
    background-color: var(--background-color);
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
    color: var(--text-color);
    transition: background-color 0.3s ease;
}

h2 {
    color: var(--primary-color);
    text-align: center;
}

#login-screen, #chat-screen {
    background-color: var(--card-background);
    padding: 30px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    width: 400px;
    display: flex;
    flex-direction: column;
    gap: 15px;
    transition: transform 0.5s ease-in-out;
}

.hidden {
    display: none !important;
}

input[type="text"], button {
    padding: 12px;
    border: 1px solid #ced4da;
    border-radius: 8px;
    font-size: 16px;
}

button {
    background-color: var(--primary-color);
    color: white;
    font-weight: bold;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

    button:hover {
        background-color: #0056b3;
    }

#messages-container {
    background-color: var(--secondary-color);
    border-radius: 8px;
    height: 400px;
    padding: 10px;
    overflow-y: auto;
}

#messagesList {
    list-style-type: none;
    padding: 0;
    margin: 0;
}

    #messagesList li {
        padding: 8px 12px;
        border-radius: 6px;
        margin-bottom: 8px;
        background-color: var(--card-background);
        box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
    }

#input-container {
    display: flex;
    gap: 10px;
}

#messageInput {
    flex-grow: 1;
}