Inkscape 0.91 on Windows 10. The zip contained some .svg files of all the icons

I changed my Inkscape to a black theme. I also changed the icons to grey; this all came in a zip file that someone had prepared. All was fine, however I saw that the icons were too dark and I couldn't see them properly. Stupidly, I opened the icons.svg file on Inkscape and changed all of them to a s...