Currently, it is not possible to specify differently CSS files for multiple screen sizes.
However, CSS itself is providing an easier way to create different UX for your screen size qualifiers files.
Consider the following scenario:
And you need to provide different styles for both pages.
What you can do is the following:
And use them accordingly where needed
the button in main-page.minWH720,xml
will have cssClass="
the button in main-page.minWH480,xml will have cssClass="
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