.header {
    background-image:
    linear-gradient(to right bottom,
   rgba(18, 206, 8, 0.8),
   rgba(30, 108, 217, 0.8)),
   url('../IMG/header.webp');

    background-size: cover;
    background-position: top;
    position: relative;
}

.white-text {
    color: white !important;
}

.black-text {
    color: black !important;
}

.vertical-center {
    margin: 0;
    position: absolute;
    top: 50%;
    -ms-transform: translateY(-50%);
    transform: translateY(-50%);
}