I am attempting to put a border around a featured article on the home page.

Unable to set padding because it is overridden by

@supports (display: grid){
.blog-items .blog-item {
padding: 0;
}

I've added
.blog-item {
background-color: white !important;
border: 1px solid black !important;
padding: 15px;
}
to custom.css. The background and border work perfectly but the padding setting is greyed out.

If I uncheck padding: 0; in
@supports (display: grid){
.blog-items .blog-item {
padding: 0;
}
then padding: 15px; works but I'm unable to permanently change the "padding: 0;" setting.

I hope I've explained this clearly. Thanks in advance, Keith