Adjust the image column on mobile view

Site URL: https://www.bauyu.com/kol-experiences

The mobile view of this page is like the second attachment below, which shows only one item in a row. 

I want to display two items in one row, is it possible to do so? 

Add to Design > Custom CSS

/* Mobile Influceners 2 columns */
@media screen and (max-width:640px) {
section#influencer-gallery-01 .span-3 {
    width: 50% !important;
    float: left !important;
}
section#influencer-gallery-01 .span-3:nth-child(2n+1) {
    clear: left !important;
}
}