(Help) Seeking Help with a Circular Fill Animation Effect

Hello Reddit-Unity community!

I recently came across an intriguing visual effect in a video and have been racking my brain trying to figure out how to replicate it. The effect isn't about the flood fill algorithm itself, but specifically an animation where the color spreads evenly from the center to the edges in a circular manner. It's captivating!

Here's the video for reference: https://www.youtube.com/watch?v=adCPFnvEqa0&t=14s

Does anyone have any insights on how this can be achieved? Is this done using shaders or some other technique? Any guidance or pointers would be greatly appreciated.

Thanks in advance for your help!