How to runtime position controls?

I am using asp.net 2.0. 

I have four controls on the top of the page. The most left is a label, and then there are two dropdownboxes, the most right end is a button.

The two dropdown bind to data. So each time when the page load, the values might be different, so the dropdown widthes are different at each time.

I want there are 10px space between each control.

Also when I change the first dropdown the value in the 2nd sropdown changed. Therefore I need change the last button's position.

So I think I need a UpdatePosition function and that need to be called at page load and dropdownbox selectedIndexChanged handlers.

How can I do it? 

 

 
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