#first{
	margin:0 auto; 
}
#a{
	width:120px; 

}
#first_a{
    width:auto;
	border:1px solid #CCC;
	margin-left:0px;
	position:absolute;
	z-index:2522;
	background:#FFFFFF;
     	
}
#first_a tr:hover{
	background:#969;
}
#first_a table{
	width:100%;
}
#first_a{
	display:none;
}