Brine Mobile view summary block change to 2 columns

Site URL: https://fishyfishyfishkeeper.com/collections

I want to change my 5 column Summary block, into a 2 column on mobile view. Please help! Lemme know what CSS code to insert. 

I don't know the description for summary blocks. 

Add to Design > Custom CSS

/* Collections mobile 2 items */
@media screen and (max-width:767px) {
div#page-section-61876cda1189e657e318ec4a {
.summary-item-list {
    height: auto !important;
}
.summary-item {
    position: relative !important;
    top: unset !important;
    left: unset !important;
    width: calc(~"50% - 20px") !important;
    margin-right: 20px;
    height: auto !important;
    float: left !important;
}
}
}