.img-secundaria-cursor {
    position: relative;
    width: 100%;
}

.img-secundaria-cursor .img-a,
.img-secundaria-cursor .img-b {
    width: 100%;
}

.img-secundaria-cursor .img-b {
    position: absolute;
    opacity: 0;
    top: 0;
    left: 0;
    pointer-events: none;
    transition: filter 0.3s ease, opacity 0.3s ease;
}

.img-secundaria-cursor:hover .img-b {
    opacity: 1;
}