Oops, using Canvas instead of a child theme but you’re going to upgrade Canvas. No worries.
You were on the right track using Canvas, but you forgot to use a child theme. A what? Yeah, I know. But if you’re going to ever upgrade Canvas (and you should), then it’s going to make life easier for us all (not to mention your website) to use a child theme for your tweaks, changes, and CSS custom styling. Here’s a primer on how to add that child theme back in after you’re already using Canvas. Hint, it’s easy.