function init() {
IE = (document.all)
NC = (document.layers)
Opera = (document.getElementById)
}

function hiddenLayer() {
init();
if(IE) eval('document.all["file-sk"].style.visibility = "hidden"')
if(NC) eval('document.layers["file-sk"].visibility = "hidden"')
if(Opera) eval('document.getElementById("file-sk").style.visibility = "hidden"')
}

function showLayer() {
init();
if(IE) eval('document.all["file-sk"].style.visibility = "visible"')
if(NC) eval('document.layers["file-sk"].visibility = "visible"')
if(Opera) eval('document.getElementById("file-sk").style.visibility = "visible"')
}