var EffectImages = new Array();
    
    function EffectStart(id){
        EffectImages[id] = document.getElementById(id).getElementsByTagName('DIV');
        if (EffectImages[id].length){
            for (var i = 0 ; i < EffectImages[id].length ; i++){
                EffectImages[id][i].style.zIndex = i+1;
                EffectImages[id][i].style.visibility = 'visible';
            }
            EffectImage(id,EffectImages[id].length-1);
        }
    }
    function EffectImage(id,imageIdx){
        if (imageIdx < 0){
            imageIdx = EffectImages[id].length-1;
        }
        EffectImageFade(id,imageIdx);
    }
    function EffectImageFade(id,imageIdx){
        new Effect.Opacity(
            EffectImages[id][imageIdx],
            {
                'duration':4,
                'from':1,
                'to':0,
                'afterFinish':function () {
                    for (var i = 0 ; i < EffectImages[id].length ; i++){
                        var e = EffectImages[id][i];
                        EffectImages[id][i].style.zIndex++;
                    }
                    EffectImages[id][imageIdx].style.zIndex = 1;
                    new Effect.Opacity(EffectImages[id][imageIdx],{'from':1,'to':1,'duration':0});
                    window.setTimeout(
                        function() {
                            EffectImage(id,imageIdx-1);
                        },
                        2000
                    );
                }
            }
        );
    }
    
    function initEffects(){
        if(document.getElementById('effect') != undefined){
            EffectStart('effect');
        }
    }
    
    addLoadEvent(initEffects);