There are several settings related to High contrast in Windows 8.1. They are located in PC Settings -> Easy of Access -> High contrast.
Using these settings, it is possible
- to set the background color for windows and documents
- the hyperlinks color
- the disabled text color
- the color of the text selection
- ... and some other settings.
If you would like to have a shortcut which will allow you to open those settings directly, here are simple instructions.