Text not wrapping in smartphone display

I’m using the aegaeus theme and two plugins – grid gallery with custom links pro and media library custom fields to produce a gallery style menu at http://torontobicycletours.com/scheduled-tours/. Things look okay until I try to view on a smartphone or in a narrow browser window (see attachment). The caption text below each image stops wrapping and the display looks unsightly. How do I fix this issue?

Thanks,
Terrence