• https://superuser.com/a/1185870/141252

ls /sys/module/vt/parameters/default_{red,grn,blu} | while read file; do cat "$file" | tr ',' '\n' | while read num; do echo -n "$((255 - $num)),"; done | sed 's>,$>>'; echo; done | tee inverted_colors
 
sudo setvtrgb inverted_colors