Understanding of how style manager implements and handle CSS

Issue 1

I made a page using grapesJS and then I exported the page and then imported it back. On importing whatever styles I had applied I am not able to see the styles in the style manager.

Issue 2

Due to issue 1 on applying new styles since I do not see what earlier styles I applied, in some cases, I can see them in the view but on deploying the page I am not seeing the changes done. (p.s. I think probably it's due to CSS conflicts. 2 or more classes are being applied and both of them are trying to change the same attribute, thus choosing one). So on what basis is class is being chosen and is there any way to resolve it.

Issue 3

So by default grapes supports 3 views. Desktop, tablet, and mobile. So on changing views I believe I can different CSS for all different views. So I tried implementing some CSS on different views. In some cases, the changes could be seen as expected on changing views, but in some cases, it is changing the complete CSS irrespective of the view. So is there any logic to it? On what things different stylings can be applied and can be maintained differently for other views and what are attributes can be changed like this?

Any help or clarity will be appreciated.

Thank You in advance.