Wherever possible, styling has been applied within the sections, rows and modules themselves, however, each layout also has both a Global CSS and Page CSS fullwidth code module at the top of the page.
The contents of the Global CSS module is the same on each page, the contents of the Page CS module is different for each page.
If you wish, you can copy and paste the contents of the Global CSS module (leaving out the <style> </style> tags) to your child theme stylesheet or Divi Theme Options Custom CSS box, and then delete the module from your pages. You only need to do this from a single layout and can then delete the module on all layouts.
You can also do the same with the Page CSS content, but you must do this on each layout as the CSS is different per page.
If you decide to move all the CSS to your child theme stylesheet or Divi Theme Options Custom CSS box, you can delete the entire fullwidth section on each layout.
There is a backup of the styling in the unzipme_seraphina.zip file broken into sections, should you need it.