The first example of not using absolute positioning isn't a good example because sometimes you do need to absolutely position things, like a modal.

Also you can just use display: flex with justify-content: center and align-items: center for non absolutely positioned elements.

Just because it uses CSS grid does not make it more "correct" than flexbox.

I also only see one usage of custom @property properties here, which has been one of the most useful things to happen to CSS in years. They have many different use cases, particularly for complex animations.