Hi there,
there are the set % sizes for desktop, tablet and mobile in the LGC Shortcode.
If you want to specify something between those ranges then you could try a media query with some CSS eg.
@media (max-width: 800px) and (min-width: 640px) {
#generate-section-6 .lgc-column:first-child {
width: 30%;
}
#generate-section-6 .lgc-column:nth-child(2) {
width: 70%;
}
}
So this will change the first column in that section to 30% and the second to 70% between those breakpoints. Adjust the sizes accordingly