Edit Mode for different Browsers Sizes
Since the Foundation theme is geared to Mobile first, there is a way to for you to edit the your page in other browser modes.
In the Site Styles stack, there is a section called Foundation - Edit Mode
Here you can choose the browser size:
And if you choose a custom size, the settings will change and look like this:
Choose the mode you want to use and it will change the way Edit mode looks, below is an example of Edit Mode set to Mobile (320):
Now you can see the edit mode of any mobile or desktop size you want.
Now go forth and make your websites great!