[refactor] Add colors for verse number markers

Current:

<img width="206" height="157" alt="Image" src="https://github.com/user-attachments/assets/80961834-486c-46dd-92bc-285b13d7a5cc" />

Expected:

<img width="138" height="75" alt="Image" src="https://github.com/user-attachments/assets/08c235da-936b-48f1-9059-dd34d0bcc276" />