Front Page – Featured Page problem

Hi – I am using your theme and like it for my website owenjacobs.com. I had to change some featured pages in the Featured Page section on the front page. It looks fine in the Customizer but misbehaves in the browser (Chrome). Depending on how you resize the page, the 4th featured page item sometimes goes on its own line and the 5th and 6th item below on a new line. The first line of 3 items is always O.K. – always on the same line.
Please let me know how to fix this problem. I do want 6 featured pages in the section – 3 on one line, 3 on the next line.

The page I need help with: [log in to see the link]