Ie and ff are different. If you want to block it successfully in ie, you must add a background to the upper-layer label; otherwise, the background is invalid. If you do not add a background to ff Plus, you can.
A. showdetaillnk {position: absolute; top: 0; left: 0; width: 220px; height: 20px; z-index: 100; opacity: 0; background: # ffffff; filter: alpha (opacity = 0 );}
. Flash_container {position: relative ;}
<Div class = "flash_container">
<Object style = "visibility: visible;" id = "SC _httpd_requestcount"
Data = "static/flash/chart/chart.swf" type = "application/x-shockwave-flash" width = "220" height = "10">
<Param value = "opaque" name = "wmode">
<Param value = "get-data = getdata & amp; id = httpd_requestcount" name = "flashvars">
</Object>
<A title = "Click to view details" href = "webpage effects: void (0);" class = "showdetaillnk"> </a>
</Div>