Make header logo to shrink on scroll?

The header logo on our website won’t shrink on scroll. I’d like the logo to get a lot smaller when you scroll down, but not disappear completely. We have tinkered around but can’t figure it out.

Our homepage: https://www.thepeakok.com/

Since the width and height are being set on the image, you would need to use !important in the css. Right now I’m seeing that you are applying a height of 50 when you scroll. Just change that to

height: 50px !important;

and it should work. That said, it will probably sqush the image. You would be better to change the width instead (again using !important, so for example

width: 200px !important;

)