function anfahrtsskizze() {
  var win = window.open("images/karte2.gif", "Anfahrtsskizze", "innerHeight=523,innerWidth=560,height=523,width=560,resizable=No,status=No,scrollbars=No,titlebar=No,toolbar=No");
}

function nav_aktiv(id, img) {
  document.getElementById(id).src='images/' + img + '_aktiv.gif';
}

function nav_inaktiv(id, img) {
  document.getElementById(id).src='images/' + img + '.gif';
}

//function swap_image(id, img) {
//  document.getElementById(id).src='images/' + img;
//}


// Scrollbar
var scrollspeed = 20; // kleiner = schneller
var textheight = 310; // textfeld hoehe
var container;
var scrollpos = 0; var scrollpos2 = 0;
var scroll = 0; // 1 down, 2 up
var scroll2 = 0;
var win;

function startup() {
  container = document.getElementById('main');

  if( container.scrollHeight <= textheight ) {

    document.getElementById('scroll-up').style.visibility = 'hidden';
    document.getElementById('scroll-down').style.visibility = 'hidden';

  }

}

function scrolltext() {

  if( scroll == 1 && scrollpos <= (container.scrollHeight - textheight)) {
    scrollpos += 2;
    container.scrollTop = scrollpos;
    window.setTimeout('scrolltext()', scrollspeed);
  }
  else if( scroll == 2 && scrollpos >= 0 ) {
    scrollpos -= 2;
    container.scrollTop = scrollpos;
    window.setTimeout('scrolltext()', scrollspeed);
  }
}

function scrolldown() {
  scroll = 1;
  scrolltext();
}

function scrollup() {
  scroll = 2;
  scrolltext();
}

function scrollstop() {
  scroll = 0;
}