Sub-category pages 3-across rather than 2-across

Is there an easy way to change the css to show sub-category pages not 2-across but 3-across?
I have many sub-categories and want to condense the listings. I have looked at the css but am not quite sure where to start.

Thanks for any help.

Hi Forestry1,

Please just add the code below in the 'administration-->Nop Templates--> Themes-->Alfresco-->Custom Head Styles':

@media all and (min-width: 981px) {

.sub-category-grid .item-box:nth-child(2n+1) {
    margin-left: 16px ;
}
.sub-category-grid .item-box:nth-child(3n+1) {
    clear: both;
    margin-left: 0 ;
}
.sub-category-grid .item-box {
    width: 210px;
}
.sub-category-grid .item-box .picture {
    width: 210px;
    height: auto;
}

}

This will make your sub-categories 3 per row on the desktop resolution.
If you need more help please write us back.