CSS body background image fixed to full screen even when zooming in/out

Hi Guyz.. I solve this problem using : background-size:cover

That is it full set of css is

body { 
background: url('images/body-bg.jpg') no-repeat center center fixed;

-moz-background-size: cover;

-webkit-background-size: cover;

-o-background-size: cover;

background-size: cover;

} 

Latest browsers support the default property.