Is there any way I can use Depth of Field as a mask for Split Toning? (Color instead of blur)

I’m trying to achieve something that would gradually turn the screen purple, kind of like a color wave that begins at the start of the view and extends to far away.

Here is a demonstration I made on Photoshop:


It is kind of like increasing the “Start” value in DoF options, except the blurry part should be swapped by the normal view and the normal view of DoF should be the purple part in this case.

I don’t have much experience in Shader Graph so it is hard for me to figure it out. If you have any ideas, I would love to know!