var klappenbild = new Image;
klappenbild.src = "layout120_nurdeckel.gif";
var impressum = new Image;
impressum.src = "impressum_(o).gif";

function OpenNav() {
    document.getElementById( 'nav' ).style.display = 'block'; }

function CloseNav() {
    document.getElementById( 'nav' ).style.display = 'none'; }

function imgHover( img )
{
    var s = img.src;
    var e = s.substring(s.length-4);
    var h = '_(o)';
    
    if ( s.substring( s.length - e.length - h.length ) == h + e ) {
        img.src = s.substring(0, s.length - e.length - h.length ) + e; }
    else {
        img.src = s.substring(0, s.length - e.length ) + h + e; }
}