简单实用特效代码，打开一个层后可以拖动
<style type="text/css">body {margin: 0px;}#div1 {display: none;position: absolute;z-index: 1000;height: 100%;width: 100%;background: #000000;filter:Alpha(opacity=30);}#div2 {display: none;position: absolute;height: 100%;width: 100%;padding-top: 10%;z-index: 1001;}#div3 {display: block;position: absolute;z-index: 999;}</style><script type="text/javascript">//定义移动对象和移动坐标var Mouse_Obj="none",_x,_y;//拖动对象函数(自动)document.onmousemove=function(){if(Mouse_Obj!=="none"){document.getElementById(Mouse_Obj).style.left=_x+event.x;document.getElementById(Mouse_Obj).style.top=_y+event.y;event.returnValue=false;}}//停止拖动函数(自动)document.onmouseup=function(){Mouse_Obj="none";}//确定被拖动对象函数 o为被拖动对象function m(o){Mouse_Obj=o;_x=parseInt(document.getElementById(Mouse_Obj).style.left)-event.x;_y=parseInt(document.getElementById(Mouse_Obj).style.top)-event.y;}</script><div id="div1"></div><div id="div2" onmousedown="m(this.id)" style="left: 0px;top: 0px;"><table width="50%" border="0" cellpadding="3" cellspacing="1" style="background: #ff7300; position:static;filter:progid:DXImageTransform.Microsoft.DropShadow(color=#666666,offX=4,offY=4,positives=true)" align="center"> <tr style="cursor: move;"> <td><font color="#FFFFFF">温馨提示：</font></td> <td align="right"><input type="button" value="ｘ" onClick="document.getElementById('div1').style.display='none';document.getElementById('div2').style.display='none';" style="cursor: hand;"></td> </tr> <tr> <td colspan="2" width="100%" bgcolor="#FFFFFF" height="150" align="middle">欢迎访问 <a href="http://www.knowsky.com">http://www.knowsky.com</a></td> </tr></table></div><div id="div3"><input type="button" value="打开层" onClick="document.getElementById('div1').style.display='block';document.getElementById('div2').style.display='block';"></div>
