Hemlock Theme: Grid Layout Problem

Hello everyone,
I am running Hemlock theme, which as I understand is supposed to have a 3-column grid. Mine only runs two oddly-aligned columns with a ton of white empty space on the left margin. I am just an intermediate WordPress user, so I can edit .css but don’t always understand where to locate a problem. Any help would be amazing.

https://doesithavebooze.com

Thanks!