When you view a type of file which lesspipe.sh sends through code2color for syntax highlighting, it assumes that the file will be displayed on a white background. This is very annoying when the terminal background happens to be dark, which I think is the more common configuration these days, because then the dark-colored text is nearly impossible to read. None of the documentation mentions any way to change this behavior (AFAICT), and the only workaround is to disable highlighting entirely with the -L switch to less.
create a local config file ~/.code2html.config