Could you please share the ground fog shader code or link?

[DAE WOO Ryu]

Hello.
I'm having a hard time implementing the ground fog as a shader.

Could you please share the  ground fog shader code or link?

please.. help..

Based on this I am referencing the link below to implement a height based ground fog.

https://www.iquilezles.org/www/articles/fog/fog.htm

The effect we want to implement finally is to implement the effect as shown in the link below.

http://www.prepar3d.com/wp-content/uploads/2013/10/v2ExampleFog2On.jpg

I've been trying in a number of ways, but the results are still not very good.