Different logo on home page

My home page has a dark background image. All the other site pages have white background. I need a logo with white text on the home page, and black text on all the rest.

Home page uses a styled ‘Hero’ block with the global ’Nav’ area disabled. All other pages using the global ‘Nav’ area with a ‘Nav’ block. The image in the ‘Hero’ block seems to be linked to the image in the ‘Nav’ block, so changing one changes the other.

How do I do this? - Thank you.