Can I control the Caption display position in Wells?

Anyone know how I can stop the captions from jumping from the left side of the page to the right when looking at the site on a small screen? it's hard to explain in words but check out:

https://alison-shuman.squarespace.com/minarets-and-onion-domes

if you see the caption on the left, make the browser window smaller.

thanks in advance!