If you define your CSS settings in the Designer Pro clearly enough, there shouldn't be a whole lot of styling needed unless you are needing to emphasize something for a holiday or a special or something. All the main styling in the shop's CSS file will be picked up automatically. Now.... having said that lol....
If you find that you need extra styling that can be done via the HTML Tool and you can do it inline without any difficulty at all or you can define a css page using the HTML Tool and include it into head tags like you would on any website page so you would enter something like:
<head><link rel="stylesheet" href="file_name_and_location.css" type="text/css" media="screen" charset="utf-8" /></head>
You would just put that into the HTML Tool and it will end up most likely showing on your page with the [[[ ]]] brackets around it so you can ignore it after that.
Personally I change my specials and holiday stuff too much to rely on a CSS so I've used inline for the most part for anything I needed to be different than the norm. Hope that helps
