Problems with cell lines in HTML/CSS table
 

I'm trying to create a table using HTML as well as some CSS, and I've run into two problems.

First, I've noticed that when I define a color for the lines in between the table cells, it actually makes them two different colors, one of which is your specified color and the other is another color which goes well with the first. In tables, this is pretty unnoticeable and makes it look nicer, in my opinion. However, the computer seems to always decide the second color by itself; is there any way to specifically define both colors?

Also, when I open my code with Chrome or Safari, it appears to work fine; however, all the cell lines are missing with both Firefox and Opera (having a Mac, I can't test IE). What could be causing this? I know this is the type of problem in which I'd most likely have to post all of my code for it to be resolved, but since this is a school assignment, that'd be going against forum rules. Any advice as to what might be causing this problem?

If you can think of anything that might solve either question, please let me know. Thanks in advance!

It would help if you posted the CSS and html for the problem

I would, but I have a problem with that. I'm home schooled, but the curriculum comes from a popular online school. I'm afraid that students in the same class as me, while researching the same problems I have been having, might stumble upon this thread, see my code for the assignment, and at least partially steal it as their own. I don't want to contribute to possible cheating.

Do you mind if I PM it to you?

Found an answer to a similar question HERE. Many people do not code a table correctly much less make one using CSS. There are table tags that are left out, cells improperly inserted (empty cells need at least a non-breaking space), etc.. A table example.