Warning `Using kebab-case for css properties in objects is not supported`

### Steps to reproduce
Use the component in a react app

### Screenshot of the warning
<img width="539" alt="image" src="https://github.com/devfolioco/react-otp-input/assets/17308695/c69a479f-2000-46c9-a6f9-b647a5014d12">

### Possible cause: 
https://github.com/devfolioco/react-otp-input/blob/90a7b4f8a93e0209dcfe48d5f95706200241a570/src/index.tsx#L14