Website returns `404` response due to missing styles.css file

We have an automatic URL checker on one of our websites, and it's been indicating the Love Replications Week URL returns a 404. I traced it down to a missing `styles.css` file which appears to be included in your `_quarto.yml` file, but does not actually exist in this repo.

Start by checking _quarto.yml and the repository for the referenced styles.css path. Confirm whether the stylesheet should be added or the stale reference removed, then verify that the Love Replications Week URL no longer returns 404 with the automatic URL checker.

Written by the indexing model from the issue text.