Header image scaling wrong

[wicked_s2k]

My header image and white area are not the width they are supposed to be I have been messing with this for an hour or so to no conclusion. Can anyone help me with this little issue thanks. Below is the CSS for it. Both are currently measuring at 985px not the 1100px they are supposed to be.

EDIT** RESOLVED ISSUE, cause of problem firefox zooming was scaling them when I took screens to measure. Didn't realize this till looks at page on different machine.

#white_area {
	background-color: #FFFFFF;
	margin: -10px auto 0px auto;
	width: 1100px;
	height: 1060px;
}
#head {
	position: absolute;
	margin: 0px auto 0px auto;
	background: url(../images/home/lau_index_header.png) no-repeat;
	width:1100px;
	height: 202px;
}