Plugin or CSS that will change logo on some pages

I’d like to be able to change the site logo on a few pages. I checked with the theme developers; they said to look for a plugin. I found a plugin in the repository but it’s outdated (and didn’t work).

The best I did figuring out the css shifted the logo to the left and removed the navigation bar.

.page-id-1020 #page-header {
   content: url(https://www.....png);
}

Any ideas?

The page I need help with: [log in to see the link]