header {
   position: absolute;
   z-index: 1;
   width: 100%;
   top: 50%;
   left: 50%;
   text-align: center;
   transform: translate(-50%, -50%);
    -webkit-transform: translateY(-50%, -50%);
    -moz-transform: translateY(-50%, -50%);
    -ms-transform: translateY(-50%, -50%);
    -o-transform: translateY(-50%, -50%);
}

header img {
   width: 800px;
   max-width: 75%;
   height: auto;
   margin: 0 auto;
}

main {
    padding: 40px;
    overflow: hidden;
}

.slide {
    background-size: cover;
    background-position: center center;
    background-repeat: no-repeat;
    background-color: #e40613;
    width: 100%;
    height: calc(100vh - 80px);
}


@media only screen and (max-width: 768px) {
    main {
         padding: 20px;
    }

    .slide {
        height: calc(100vh - 40px);
    }
}