function imgviewer(){
        $('content_img1').morph('height:400px;');
        $('start').style.display = 'none';
    }
    
    var l = 4;
    var wimg = 100;
    var a = 4;
    var go;

    function imgchange(n){
        if(l != n && n > 0 && n < max){
            $('imgcon'+l).fade({ duration: 0.5 });
            $('imgcon'+n).appear({ duration: 0.5 });
            $('desc'+l).style.display = 'none';
            $('desc'+n).style.display = 'block';
                if(n>l){
                    go = (n - l) * wimg;
                    //alert(go);
                    new Effect.Move('thumbs_bar', { x: -go, y: 0, duration: 0.2 });
                }else{
                    go = (l - n) * wimg;
                    //alert(go);
                    new Effect.Move('thumbs_bar', { x: go, y: 0, duration: 0.2 });
                }
            a = n;
            l = n;
        }
    }
    
    function previmg(){
        imgchange(a-1);
    }
    function nextimg(){
        imgchange(a+1);
    }
    
    function containsDOM (container, containee) {
      var isParent = false;
      do {
        if ((isParent = container == containee))
          break;
        containee = containee.parentNode;
      }
      while (containee != null);
      return isParent;
    }

    function checkMouseEnter (element, evt) {
      if (element.contains && evt.fromElement) {
        return !element.contains(evt.fromElement);
      }
      else if (evt.relatedTarget) {
        return !containsDOM(element, evt.relatedTarget);
      }
    }

    function checkMouseLeave (element, evt) {
      if (element.contains && evt.toElement) {
        return !element.contains(evt.toElement);
      }
      else if (evt.relatedTarget) {
        return !containsDOM(element, evt.relatedTarget);
      }
    }