function MostrarDivGris() {            
    var Ancho = 0, Alto = 0;
    Ancho = document.body.scrollWidth;         
    var navegador = navigator.appName
    if (navegador == "Microsoft Internet Explorer")    
        Alto = document.body.scrollHeight;   
    else    
        Alto = window.innerHeight + window.scrollMaxY;
           
    document.getElementById("Poliresinas").style.display = ('none');
    document.getElementById("divGris").style.width = Ancho + "px";
    document.getElementById("divGris").style.height = Alto + "px";
    document.getElementById("divGris").style.visibility = "visible";
    document.getElementById("divGris").style.display = "block";              
    document.getElementById("divGris").style.zIndex = 999;
}

function OcultarDivGris() {        
    document.getElementById("divGris").style.visibility = "hidden";
    document.getElementById("divGris").style.display = "none";
    document.getElementById("ContenedorFlash").style.display = ('none');
    document.getElementById("Poliresinas").style.display = ('block');
    document.bgColor = ("#D8D8D8");
}