area
<DIV ID=plane1 align="center">
<map name="planePic1Map">
<area shape="circle" coords="302,184,10" href="#" style="background-image:url(1.gif) background-position:center padding:inherit visibility:visible" >
</map>
<img src="map1.jpg" name="planePic1" width="988" height="685" border=0 usemap="#planePic1Map" onmousewheel="return bbimg(this)"></DIV>
为何area背景图片无法显示?