body {
    background-color: #121212;
    color: #ffffff;
    font-family: 'Roboto', sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}

.scanner-container {
    text-align: center;
}

h1 {
    margin-bottom: 20px;
}

#preview {
    width: 100%;
    max-width: 400px;
    height: auto;
    border: 2px solid #00ff00;
    border-radius: 10px;
    margin-bottom: 20px;
}

#message {
    font-size: 1.2em;
    color: #ff0000;
}