To add a black overlay on Product block on hover, you can use this code to Custom CSS box.
If code doesn’t work, you can comment below, message or email me.
div.product-block .image-container a:after {
content: "";
background-color: rgba(0,0,0,0.75);
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
opacity: 0;
transition: all 0.3s ease;
}
div.product-block:hover .image-container a:after {
opacity: 1;
transition: all 0.3s ease;
}
Result
To change overlay color, change this line.
