.jarallax {position:relative;z-index:0;}
.jarallax > .jarallax-img, jarallax-img img {display:block;position:absolute;left:0;top:0;width:100%;height:100%;z-index:-1;object-fit:cover;}

.jarallax-keep-img {position:relative;z-index:0;}
.jarallax-keep-img > .jarallax-img {display:block;position:relative;max-width:100%;height:auto;z-index:-100px;opacity:0;}

.jarallax {min-height:600px;}