Hi there,

Welcome to SeaTheme forum.

For the specific post, please add the CSS to you child theme:

@media (min-width: 768px) {
 .postid-839 .list-layout-col2 {
   display:flex;
}
 .postid-839 .list-layout-col2:after:
 .postid-839 .list-layout-col2:before{
  display:none;
}
 .postid-839 .list-layout-col2-item {
    width: 25%!important;
}
 .postid-839 .list-layout-col2 .ux-lazyload-wrap {
    width: 100%!important;
    height: auto!important;
 }
}

If all of your gallery posts are with the same layouts(4 columns), please add the CSS:

@media (min-width: 768px) {
.list-layout-col {
   display:flex;
}
 .list-layout-col:after:
 .list-layout-col:before{
  display:none;
}
 .list-layout-item {
    width: 25%!important;
}
 .list-layout-col .ux-lazyload-wrap {
    width: 100%!important;
    height: auto!important;
 }
}

Regards!
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