?window.onload=function(){?? ??? for(var i=0;i<100;i++)?? ??? { ?? ????? var em=document.createElement('span');?? ??? ? em.id="snow";?? ??? ? em.innerText="*";?? ??? ? document.body.appendChild(em);?? ??? ? snow(em); ?? ??? ?? }?? ?? }? ? ? function snow(obj){?? ??? var speedY=Math.random()*3+2;?? ??? var speedX=4-speedY;?? ?? ??? ??? var w=document.body.clientWidth-obj.offsetWidth;?? ??? var h=document.body.clientHeight-obj.offsetHeight; ???? ? ? ? var otop=obj.style.top; ?? ??? var oleft=obj.style.left;????? otop=speedY+'px';?????? //不報錯?? obj.style.top=speedY+‘px’;??? //報錯為什么呢？？？？？？？？