Hello!
Thanks for the excellent question. You’re right, in BoldGrid Resolve, the background image is only given its full height on the front page to make room for a call-to-action widget.
If you’d like to get your other pages to follow the same look and feel, you can do this with a custom JavaScript in your Customize > Advanced > Custom JS & CSS. Paste the following snippet into your Custom Theme JS box:
jQuery('body.page-template-default #masthead > div:nth-child(3)').addClass('mod-space-home');
I hope this helps!