How to use gridlover.net as a designer?

Question

css

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1. How to use scale factor correctly?
2. Where to use the generated css styles? How should a designer use them? I know the layout, but how to use this css when creating layouts?
3. How critical is it to use vertical rhythm in grids?

Answer 1

I answer:
1. turn the slider with the mouse
2. into the style.css file and then connect it to the page
3. criticality also depends on perception