I’m testing out these styles for Hacker News using PageExtender for Safari (because I use Safari). But, I tweaked a few of the styles with the following ruleset changes.

#hnmain td {
  background-color: #101820
}
.title {
  font-size: 1rem
}
a:link {
  color: #efefef
}
.comhead {
  padding: .75rem 0 0.75rem 0
}