最后一張跳轉到第一張是成功的但，為什么最后一張圖片顯示不了，出現空白頁。

function?pic_play(offset){
			var?newLeft=parseInt(picPlay_11.style.left)?+?offset;
		
			picPlay_11.style.left=newLeft+'px';
				if(newLeft?>?-900){
					picPlay_11.style.left?=?-5400?+?'px';
				}
				if(newLeft?<?-5400){
					picPlay_11.style.left?=?-900?+?'px';
				}
		}
		next.onclick=function(){
			pic_play(-900);
		}
		prev.onclick=function(){
			pic_play(900);
		}


?<div?id="picPlay_11"?class="picPlay_1"?style="left:-900px;">
	?	<img?src="images/play/6.png"alt="6"/>
	??	<img?src="images/play/1.png"alt="1"/>
	??	<img?src="images/play/2.png"alt="2"/>
		<img?src="images/play/3.png"alt="3"/>
		<img?src="images/play/4.png"alt="4"/>
		<img?src="images/play/5.png"alt="5"/>
		<img?src="images/play/6.png"alt="6"/>
		<img?src="images/play/1.png"alt="1"/>
		
	??</div>