#page_side_btn {
	position: fixed;
	top: 20px;
	left: 50%;
	margin-left: 407px;
	width: 50px;
	overflow: hidden;
}
#page_side_btn li {
	float: right;
	margin-bottom: 4px;
	line-height: 1;
}
#page_side_btn a:hover img {
	opacity: .8;
	filter:progid:DXImageTransform.Microsoft.Alpha(Opacity=80);
}