body, html {
    height: 100%;
}
.bg {
    background-image: url('/static/images/background.jpg');

    height: 100%;

    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
}
.overlay {
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    color: white;
    text-align: center;
}
h1 {
    font-size: 4rem;
}
p {
    font-size: 1.5rem;
}
.btn-custom {
    margin-top: 20px;
    font-size: 1.2rem;
}