Maybe the interface of WP varies from version to version, I don’t know but I can’t find anything like that. Neither theme options nor basic settings. All what I see is Customize. When I go there, I can hide Header text (site title) and upload Header Image. But this image doesn’t appear anywhere.
I have the same problem but in my case the sizes of the boxes are equal unlike the number of text lines. In the 3rd box the text is shorter that in the others..
Actually I would prefer to hide the text (or at least be able to edit it) and keep only picture and title.
Is that possible? Otherwise I will have to search for another theme..