You can create your own CSS and we will merge it into the Turnkey application.

The file should be named tkusercss.css and reside in application-root/Content.

The tkusercss file is the correct place to introduce your new styles that match the names of the styles given in the ViewModel columns style attribute.

To do a massive reshaping of the standard look, you can override existing styles from site.css in your tkusercss.css - but a better option might be to make the site global style changes with the scss strategy described here.

If you ever suffer from FOUC https://en.wikipedia.org/wiki/Flash_of_unstyled_content, it is probably due to having styles defined too late on your page. Consider moving into tkusercss.css