.jumbotron.header {
    position: relative;
    margin: 0;
    height: 750px;
    overflow: hidden;
}
.jumbotron.header:before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: linear-gradient(180deg, rgba(0, 0, 0, 0.35) 0%, rgba(0, 0, 0, 0) 100%);

}
.jumbotron.header img {
    object-fit: cover;
    width: 100%;
    height: 100%;
}


@media (max-width:767px)
{
    .jumbotron.header {
        height: 375px;
    }

}
@media (min-width:768px) and (max-width:991px)
{

}
@media (min-width:992px) and (max-width:1199px)
{

}