多个圆的运动

/*css*/body{margin:0;padding:0;} .div1{height:50px;width:50px;background:red;border-radius:50%;position:fixed;left:0;top:0;} .ab{z-index:0;}

//js部分var conten=document.getElementById('conten'); var div1=conten.getElementsByTagName('div'); var cw=document.documentElement.clientWidth||document.body.clientWidth; var ch=document.documentElement.clientHeight||document.body.clientHeight; var timer=null; var j=0; conten.onclick=function(){ fb(); for(var i=0;i(cw-obj.offsetWidth-x)){ x=-x;obj.style.background='#efefef'; } else if(obj.offsetLeft<0){x=-x;obj.style.background='green';} if(obj.offsetTop>(ch-obj.offsetHeight-y)){ y=-y;obj.style.background='blue'; } else if(obj.offsetTop<0){ y=-y;obj.style.background='#B2D00F'; } obj.style.left=obj.offsetLeft+x+'px'; obj.style.top=obj.offsetTop+y+'px'; },20); } function fb(){ var div2=document.createElement('div'); var div2texte=document.createTextNode(''); div2.className='div1'; j++; div2.style.zIndex=j; div2.appendChild(div2texte); conten.appendChild(div2); }