// shows/hides the appropriate lightbox depending on the icon hovered on
function show(elementName){
    var elementName = elementName;
    document.getElementById(elementName).style.display = "block";
    document.getElementById(elementName).style.visibility = "visible";
}
function hide(elementName){
    document.getElementById(elementName).style.display = "none";
    document.getElementById(elementName).style.visibility = "hidden";
}