I know how to work with flexbox, grids, etc... I know how to create layouts.

But designing something from scratch that has been designed better by a framework, I don't want to do that. It's not my specialty for a reason.

I know how to customize and implements new features over frameworks like Bootstrap and Bulma. And I use Sass a lot for that purpose. But no, I won't rewrite a navbar component each time I start a new project.