[Theme: Catch Box] changing content size

Hi guys,

I’m using the catch box theme and trying to change the width of the content, as well as the width of the right panel (where it says archives, meta etc). I was told to put the following code in the custom CSS style:

#primary {
margin: 0 -22% 0 0;
}
#content {
margin: 0 22% 0 2%;
width: 68%;
}
#secondary {
width: 16%;
}

However, I’m trying to tweak the numbers but it doesn’t seem very straightforward. Sometimes increasing the numbers makes it disappear, sometimes decreasing the numbers doesn’t make it smaller. Can someone explain:

1. What #primary, #content and #secondary refer to?
2. How do I change the 4 numbers on the ‘margin’ to manipulate content and right panel sizes?

Thanks,