Change Image Width?

I’m using the Vortex theme and trying to build a gallery type page with Page Builder.

When I preview the page I’m building, the image from a row with only one column appears the same width as images from a row with four columns.

I know there is a way to make the image larger, but I can’t seem to figure it out. Perhaps something in my theme’s code is inhibiting the single column image from appearing larger?

I went ahead and published the page, to show you what I mean, but I didn’t want my (four) subscribers to get an email about a dummy page, so I published it pw protected: adgj

http://solarrainbucket.com/524-2/

Thank you for any help. I don’t speak computer very well… But I’m trying!

https://wordpress.org/plugins/siteorigin-panels/