need clarification for mobile site

[namadhuponneri]

how to edit category style in mobile site?

[Basara]

Hello.

Try to enable Template debug in System Settings and see what file you need to edit
Also you may need to edit CSS rules as well

[abantecart]

how to edit category style in mobile site?

You need to check how to use browser  HTML and CSS inspector. This will help you to locate CSS styles for mobile site.
Firefox Firebug is handy.