Jekyll deletes style link in index.html

I’m new to Jekyll, but was able to get it up and running fairly easily. I’m having an issue with Sass, however. I have my Sass file set up properly, with the FrontMatter dashes at the top of the file. I can see that it is compiling correctly, because it’s creating a css file in the assets subfolder of the _site folder. The issue I’m having is that each time I run jekyll serve from the command line, my link to the outputted css file is getting deleted, so that there’s no link to the styles. Even if I delete the original main.css file that was generated when the project was initially created, that is added back, and my own link I added gets deleted, so that I’m stuck with the base css files. Can anyone tell me what’s going on here? Thanks!

not clear to me what this means " my link to the outputted css file is getting deleted"

where is this? in the head of all your files?

You aren’t putting something in the actual _site folder are you? it gets deleted every time jekyll builds.