Hi, Shawn —
Thanks for the quick reply. I'd tried the "Having Issues?" options, as mentioned, but they didn't help. After your note, I reached out to the theme developer, but he told me to contact the plugin developer, despite me linking to this thread in my original email. ¯\_(ツ)_/¯
I played with the theme's style.css and eventually found the conflicted was caused by this declaration:
button {padding:10px 20px 5px!important;}
I removed !important, and the issue was resolved.
-Ken