Different style based on number of handle / thumbs

Currently, we have `slider-handle slider-handle-lower` and `slider-handle slider-handle-upper` to style the handle / thumbs.
This work great for slider with multiple handle /thumbs, how do I style a singler with a single handle / thumb differently ?
Exemple:

<img width="488" alt="Image" src="https://github.com/user-attachments/assets/94974b2c-932d-4454-8042-9e75fcea9d0b" />