NPM install as well as JS, SASS and purgeCss compilation are triggered when the the ASP.net solution is built.

dotnet watch

or

CTRL-F5 or F5

npm install

npm run dev

npm run build

npm run preview

npm run purgecss

npm run watch

https://vitejs.dev/

Config with Bootstrap 5 whitelisting dynamic css classes.

Thanks to swildermuth for his explanation on this great Youtube video

https://www.youtube.com/watch?v=L23bAMdgOZA