Resizing gallery grid on mobile in 7.1

Site URL: https://www.healthcareheinsman.com/wayne-heins

So I have a gallery block with some icons in it and using it to link to socials and contact and what not, but on mobile, I can't figure out how to make it to where the gallery would be on a single line like on desktop. I am sure there is a line of code I could write to force it to fit that space instead of try to be a 2x2 grid..

Add to Design > Custom CSS > Then save & reload the site

@media screen and (max-width:640px) {
div#block-yui_3_17_2_1_1661307703244_7511 .slide {
    width: 20% !important;
}
}