I am trying to make my #header background image fluid so it looks nice on any mobile devices. I am using this simulator to test my site http://transmog.net/iphone-simulator...tsunoindex.me/ the background image doesn't show the correct aspect ratio in chrome but in firefox it works fine. I don't really know if it looks fine on a real iphone. Can anyone help me fix the background?

background-image: url(images/header.jpg);
background-size: 100%;
-webkit-background-size: 100%;
-moz-background-size: 100%;
-o-background-size: 100%;
width: 100%;