Layers

I know this may make me sound like a no0b but… can someone help me understand my problem with layers…

when i use:

<div id="header" style="position:relative; width:430; height:363; z-index:1; top: -150;">
<table>content</table>

i end up with 363px of white space below the layer pushing the “content” table down…

I know i can use ‘absolute’ but my page is designed at 750px and the page is centered… so basically absolute be out of place if i resized the browser, or viewed it full screen at a different resoution…

i’d know if theres something i can use to get everything aligned right?
can i use javascript that would check the screen size and position the layer accordingly?

Thanks again…
i’ve been struggling with this issue ever since…

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