Here's a couple of edits that will pull colors from the 256-color (XTerm) palette and make the titles bold:

  blue_highlight=`echo "\033[0;38;5;68m"`                                                                                                      
  brown_highlight=`echo "\033[0;1;38;5;202m"`
  . . .
  . . . (end of script)
  echo "\033[0m"