.product-hover-image-wrapper {
    position: relative;
    overflow: hidden;
}

.product-hover-image-wrapper img {
    width: 100%;
    height: auto;
    display: block;
    transition: all 0.4s ease;
}

.product-hover-image-wrapper img.secondary-image {
    position: absolute;
    top: 0;
    left: 0;
    opacity: 0;
    visibility: hidden;
    z-index: 1;
}

.product-hover-image-wrapper:hover img.secondary-image {
    opacity: 1;
    visibility: visible;
}

.product-hover-image-wrapper:hover img.primary-image {
    opacity: 0;
    visibility: hidden;
}