How do I get my Logo to scale properly with my header height?

Site URL: https://www.prestigeautosearch.com/

I am having issues with getting my logo to properly scale with my header. I don't like how I am unable to keep my header the same size while scaling my logo. Also the built in logo scaling isn't enough to get my logo to the proper size. I've tried a couple of CSS lines but none seem to work. 

First thing you can try is to remove all the transparent space around the logo to make it bigger?

26 minutes ago, bangank36 said:

First thing you can try is to remove all the transparent space around the logo to make it bigger?

I have cropped the photo inside the editor to no avail. It doesn't seem to change it at all. I have also tried scaling the image up outside of SquareSpace but that also hasn't worked. 

1 hour ago, bangank36 said:

First thing you can try is to remove all the transparent space around the logo to make it bigger?

So after cropping it I seem to have a problem with the background. It's a PNG but as soon as I crop it the background around it turns white for some reason. 

You need to trim the background and save image as png