//控制頭部購物車的顯示
function fixshow(min_height){
min_height ? min_height = min_height : min_height = 830;
$(window).scroll(function(){
var s = $(window).scrollTop();
if( s > min_height){
$("#proBuyTip").fadeIn(100);
$(".fixtabwrap").addClass("topfixed");
}else{
$("#proBuyTip").fadeOut(200);
$(".fixtabwrap").removeClass("topfixed");
};
});
};

.topfixed {
position: fixed !important;
top: 0px;
left: 0px;
z-index: 999;
width: 100%;
background-color: white;
position: absolute;
_top: expression(eval(document.documentElement.scrollTop));
}