Center a lonely product Squarespace commerce

Hi all,
I am trying to center this calendar product on my page https://www.juliestamenic.com/calendars24
Would anyone know how to? I'd like to keep it the same size

Many thanks
Julie 

Try adding this CSS code

@media screen and (min-width:768px) {
body#collection-65523285dd6cd60d69f07324 .grid-item {
    position: relative;
    left: calc(~"150% + 1.5vw");
}
}