column-gap

CSS column-gap property can be used to specify the gap between columns

Before applying column-gap

After applying column-gap:10px

.container{
    display:grid;
    grid-template-columns:1fr 1fr 1fr 1fr;
    grid-template-rows:50px 50px 50px;
    border: 2px solid #ccc;
    padding:10px 10px;
    column-gap:10px
}