sue wrote:which program should I use to accomplish this?
Notepad will do the trick
It's just a plain text file that contains a bunch of instructions that control how the web page should look. There are heaps of programs out there that know about CSS and offer extra editing features although I don't use any of them. It's probably more important to get a handle on how CSS works first before starting to worry about which whiz-bang program you should be using to edit the files