body {
    background-color: #000; /* fond noir */
    color: #fff;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    flex-direction: column;
}

.card-dark {
    background-color: #2b2b2b;
    border-radius: 1rem;
    padding: 2rem;
}

.inner-box {
    background-color: #fff;
    color: #000;
    border-radius: 0.75rem;
    padding: 1.5rem;
    text-align: center;
}

.btn-red {
    background-color: #e60000;
    color: #fff;
    font-weight: bold;
}

    .btn-red:hover {
        background-color: #cc0000;
        color: #fff;
    }