body {
    font-family: Arial, sans-serif;
    text-align: center;
    background-color: black;
    color: gold;
    transition: background-color 0.3s, color 0.3s;
}

body.light-mode {
    background-color: white;
    color: black;
}

.wallet-container {
    width: 50%;
    margin: auto;
    padding: 20px;
    border: 2px solid gold;
    border-radius: 10px;
    background-color: rgba(0, 0, 0, 0.8);
    box-shadow: 0 0 10px gold;
}

input {
    padding: 10px;
    margin: 10px;
    width: 80%;
}

button {
    padding: 10px 20px;
    background-color: gold;
    border: none;
    cursor: pointer;
    transition: background-color 0.3s;
}

button:hover {
    background-color: darkgoldenrod;
}

#qrcode {
    margin: 20px auto;
}

#transaction-history {
    list-style-type: none;
    padding: 0;
}

#transaction-history li {
    margin: 10px 0;
    padding: 10px;
    background-color: rgba(255, 215, 0, 0.1);
    border-radius: 5px;
}

.popup {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    justify-content: center;
    align-items: center;
}

.popup-content {
    background-color: white;
    padding: 20px;
    border-radius: 10px;
    text-align: center;
}

.popup-content button {
    margin-top: 10px;
}