body {
    font-family: Arial, sans-serif;
    text-align: center;
    background-color: #f4f4f9;
    margin: 0;
    padding: 20px;
}

#generator {
    padding: 20px;
    background-color: #fff;
    border: 1px solid #ddd;
    border-radius: 10px;
    width: 80%;
    margin: 0 auto;
}

select, input, button {
    margin: 10px;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
}

#codes {
    white-space: pre-wrap;
    text-align: left;
    margin-top: 20px;
    padding: 10px;
    background-color: #f0f8ff;
    border-radius: 5px;
    border: 1px solid #ccc;
}

#copyButton {
    display: none;
    margin-top: 10px;
}

.floating-message {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background-color: rgba(255, 255, 255, 0.9);
    border: 2px solid #f0a;
    padding: 15px 30px;
    font-size: 1.5em;
    color: #f00;
    border-radius: 10px;
    animation: fadeInOut 30s ease-in-out;
}

@keyframes fadeInOut {
    0% { opacity: 0; }
    10% { opacity: 1; }
    90% { opacity: 1; }
    100% { opacity: 0; }
}