body {
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    transition: background-color 0.3s, color 0.3s;
}

body.light-mode {
    background-color: #f4f4f9;
    color: #000;
}

body.dark-mode {
    background-color: #1e1e1e;
    color: #fff;
}

.container {
    text-align: center;
    background-color: #fff;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    width: 300px;
    box-sizing: border-box;
    transition: background-color 0.3s;
}

.container.dark-mode {
    background-color: #2b2b2b;
}

input[type="text"] {
    width: 100%;
    padding: 10px;
    margin-top: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    box-sizing: border-box;
}

button {
    margin-top: 10px;
    padding: 10px 20px;
    font-size: 16px;
    color: #fff;
    background-color: #007bff;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    width: 100%;
}

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

.qr-code {
    margin-top: 20px;
}

.qr-code img {
    width: 100%;
    height: auto;
    max-width: 250px; /* Adjust max width for better fit */
    border-radius: 5px;
}

.error {
    color: red;
    margin-top: 10px;
}

.dark-mode-toggle {
    margin-top: 20px;
}

.dark-mode-toggle label {
    cursor: pointer;
}