JS Drop down menu conflicting with other page code

[Rightz]

I am playing around with a js code I got online. I'm not very good at JS. Unfortunately the JS in the head is changing the rest of the table attributes on the page. I don't want every table to be black!

Does anyone have any advice.

[DrDoc]

Give the table you want to change and ID. Then change the code to only affect the table with the particular ID.

document.getElementById('mytable') ...