Gap Between Product Items

Hello,

I would like to set a gap between product items – please see the attached image. On this forum, I have found this code:

body .products {
    margin-left: -40px;
    margin-right: -40px;
}
body .products .product {
    padding-left: 40px;
    padding-right: 40px;
}

..but it isn’t working on my side. Is that code still working or how can I set a gap? Please note, I would need to keep borders around the items.

Best Regards