tracyelaine

Ah! That worked! Also there is a bug with how the Cart page is viewed in the Editing screens. When I added the code to the Custom CSS, it didn't show the change on the edit screen after I hit "Save". I had to exit the Custom CSS page for it to update the page shown in Edit mode. I could see the change immediately on the live site though.
Your solution worked, but it was for inverting the color of the logo, i.e. white to black. I ended up using this code to change the nav bar to a color instead of changing the color of the logo, in case anyone else is looking for this option instead. 
body#cart header#header {
    color: white !important;
    background: #199A48 !important; 
}
Thanks! 

Ah! That worked! Also there is a bug with how the Cart page is viewed in the Editing screens. When I added the code to the Custom CSS, it didn't show the change on the edit screen after I hit "Save". I had to exit the Custom CSS page for it to update the page shown in Edit mode. I could see the change immediately on the live site though.
Your solution worked, but it was for inverting the color of the logo, i.e. white to black. I ended up using this code to change the nav bar to a color instead of changing the color of the logo, in case anyone else is looking for this option instead. 
body#cart header#header {
    color: white !important;
    background: #199A48 !important; 
}
Thanks! 

Hi,
Add to Design > Custom CSS
/* Cart Page Logo */ body#cart header#header img { filter: invert(1); -webkit-filter: invert(1); }