body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f9;
    margin: 0;
    padding: 20px;
    display: flex;
    justify-content: center;
}

.container {
    max-width: 800px;
    width: 100%;
    background: #fff;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
    color: #333;
}

.controls {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    margin-bottom: 20px;
    justify-content: center;
}

label {
    font-weight: bold;
    margin-right: 10px;
    align-self: center;
}

select, button {
    padding: 10px;
    font-size: 16px;
    border: 1px solid #ccc;
    border-radius: 4px;
    cursor: pointer;
}

button {
    background-color: #007bff;
    color: #fff;
    border: none;
    transition: background-color 0.3s;
}

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

#reset-btn {
    background-color: #dc3545;
}

#reset-btn:hover {
    background-color: #c82333;
}

#copy-btn {
    background-color: #28a745;
}

#copy-btn:hover {
    background-color: #218838;
}

#download-btn {
    background-color: #17a2b8;
}

#download-btn:hover {
    background-color: #138496;
}

.output-box {
    margin: 20px 0;
    padding: 15px;
    border: 1px solid #ccc;
    border-radius: 4px;
    background: #f9f9f9;
    min-height: 100px;
}

.error-message {
    color: red;
    text-align: center;
    margin: 10px 0;
}

.action-buttons {
    display: flex;
    gap: 10px;
    justify-content: center;
}

@media (max-width: 600px) {
    .container {
        padding: 15px;
    }

    .controls {
        flex-direction: column;
        align-items: stretch;
    }

    select, button {
        width: 100%;
    }

    .action-buttons {
        flex-direction: column;
    }
}