Add hover effect on big donut label

## Problem
The big donut label does not have a hover effect.

## Describe the solution you'd like
Add opacity on hover.

<img width="362" height="556" alt="Image" src="https://github.com/user-attachments/assets/0ccdb2fc-f4cd-4198-8279-02ecb8894227" />

<img width="363" height="560" alt="Image" src="https://github.com/user-attachments/assets/5a35f021-a89b-44ec-8b3e-21765f8b17cc" />