function swapBGRestore(element) {
    element.className = 'menu';
}

function swapBG(element) {
    element.className = 'menu-over';
}
function swapBGRestoreLast(element) {
    element.className = 'menu-last';
}

function swapBGLast(element) {
    element.className = 'menu-over-last';
}