.wpifc-container {
    text-align: center;
    padding: 20px;
    background: linear-gradient(45deg, #4CAF50, #8BC34A);
    color: white;
    border-radius: 10px;
}
#convertButton, #toggleDarkMode {
    background: #388E3C;
    color: white;
    padding: 10px 20px;
    border: none;
    cursor: pointer;
    border-radius: 5px;
    margin: 5px;
}
#convertButton:hover, #toggleDarkMode:hover {
    background: #2E7D32;
}
body.dark-mode {
    background: #222;
    color: white;
}