The articles are causing unneeded eye strain by using pure black with pure white.
Ian Storm Taylor recommends not using pure black.
My recommendation is to change the both article body background, as well as, text color:
I feel like at one point in the screencast series I tried making it a dark grey instead of black but I thought it was worse in stead of better. But I'm trying it now and I'm liking it.
The background color for general modules is staying white though, there is too much legacy content that depends on blending into white and I don't mind the white anyway.