Main Page overlapping header when scrolling

ok, I’ll try to explain this the best I can, and now that I think about it, this may be a CSS issue, but anyway.

my index.php page consists of a setup like this:

<?php include_once “header_template.php”; ?>

then the html content

<?php include_once “footer_template”; ?>

my header template has a logo and 2 flash movies, a flash login and an mp3 player.

now when you scroll down to see the rest of the content on the main page, some of the content starts covering up the content in the header, the google ad on the right, the slide show in the middle and the nav menu on the left, I don’t know how to explain it, but please go and check it out for yourself, I’m not sure how to fix this or even how to search google for a fix for this.

fixed it, gave my headerbar in my css a z-index of 1