Since Microsoft doesn't provide a solution, I turned to Google. Kudos to the genius who figured out how to change the HEX colors in the .dll files (see https://officethemehacker.wordpress.com/). I am merely providing a potential resource as I have not
tried this yet so I don't know if it works nor am I endorsing it. Regardless, I would always suggest making the changes yourself rather than downloading a file that you don't know the origins of.
From all the user reviews on this website and others found across Goggle, I'd say Microsoft wins the award for causing multiple generations of employees to become immediately disengaged at work. Maybe if we had 50 shades of gray it would be more exciting,
but these two shades of gray are depressing and cause me not to want to look at my monitors. The gray (regardless of shade) causes daily headaches due to lack of contrast with surrounding screen and I have my monitor brightness down to zero and the contrast
as high as I can possibly stand it. To combat this visual onslaught, I've started wearing sunglasses while I work, which is such a professional look to present to ones coworkers and senior management. I've always been Windows and Office's biggest fan (I'm
even known as the Excel guru at work), but I'll be looking at other options for my next home PC just to avoid these horrible themes.
Perhaps, Microsoft would create the "Blue" theme they had in Office 2010 for us? Something with color? Anything but gray and white? PRETTY PLEASE?!?!? We're begging.