Hi @hepabolu, you can do this by adding the cssclass property to your YAML frontmatter. So in your weekly note template, you could add the following to the top of the note:
---
cssclass: "weekly-note"
---
Then in your CSS snippet, make sure to only target pages with the .weekly-note class.
Hope that helps, and if you don’t mind sharing, I’d love to see a screenshot since I’m curious about how people use their weekly notes!