Increase Responsive Breakpoint from 641px to higher value

Hi,

I'm using Brine in 7.0 and see that at 641px viewport width, side-by-side elements respond to stack vertically instead.

This is exactly what I want, but I would like that same global behaviour to happen at 700px width, not 641px

Is there a CSS rule that I could add to do this or even some jQuery?

Thanks for any help you can offer.

Patrick

- PS - sorry I can't post the site page right now as it is under wraps for a press release next month.

Thanks! Exactly what I needed!