var gridState = "off";
function changeBG() {
    var body = document.getElementById('body');
    if (gridState == "off") {
        body.style.background = "url(images/layout/grid.gif)";
        gridState = "on";
    }
    else {
        body.style.background = "url(images/layout/pageBackground.jpg)";
        gridState = "off";
    }

    return false;
}