I would hope it’s possible with Design System, but I haven’t been able to find anything either.
If you’re using custom CSS, then it would looks something like this:
custom section under form.js
return {
"row": {
"&:not(:last-child)": {
'padding-bottom': '10px',
'border-bottom': '1px solid #d1d3d5'
}
},
}
Best,
Lukas