not working correctly in IE 7?

[BobbyRachel]

I have a outer div which is working correctly in chrome, firefox but not in IE.. I have some contents inside outer div.. to make it center aligned or middle of page i gave this width:970px; height:630px; to outer div... so that i got the contents at the center in chrome and Mozilla... but in the case of IE 7.. in IE its left aligned.. here is my css....

<style type="text/css">
body, html { font-family:helvetica,arial,sans-serif; font-size:90%; }
div.outer {  display: block; margin-left: auto;margin-right: auto;width:970px;height:630px;position:relative;}
</style>

[Excavator]

Hello BobbyRachel,
You should try validating. See the links in my signature line about validation.
There is also a link there about DocTypes, I kind of suspect you'll need that link as well.