.banner_about:before{
    width: 100%;
    content: "";
    height: 29.167vw;
    background-image: -webkit-linear-gradient(bottom, rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.38), rgba(0, 0, 0, 0.6117647059), rgba(0, 0, 0, 0.8), #000000);
    z-index: 0;
    position: absolute;
}

header {
    height: 55%;
    min-height: 50%;
}

@media (min-width: 401px) and (max-width: 740px) {
    header, .contact_intro-3 {
        height: unset;
        min-height: unset;
    }


}