Option to remove shadow from the clock styles

Currently, all the available clock styles have a shadow effect that can sometimes reduce clarity, especially on certain wallpapers or minimal setups. Adding an option to remove or adjust the shadow intensity would make the clock look cleaner and more readable in various lighting conditions.

This would also help users who prefer a flat, modern aesthetic or want the clock to blend better with their wallpaper. Having control over the shadow effect means more personalization and a sharper look overall.