Adjust page hierarchy styles to avoid elements moving

We can make the page hierarchy (or layers) feel more robust by adjusting the styles in a way where elements are not moving around between state changes. We should consider both focus / active styles, as well as drag and drop.

Is this enough information for you to act on this, @balintbrews or @jessebaker?

Nice one @gauravvvv! I was thinking that we probably should follow the design from the preview canvas drag and drop. This means using the blue border to highlight where an element is going to be moved. Here's an example of how this could look like in the page hierarchy:

Closing this issue as a duplicate because #7 makes sense to be addressed as a part of 📌 Refine dragging behavior and design in Layers menu Active so the layers dragging can be holistically tested and reviewed.