子菜单没有出现在IE9中

Question

我的wordpress设置中有一个子菜单，IE9中出现了一个问题。它显示外部阴影，但不显示菜单本身。菜单设置在display: none;上以开始。

/* Navigation */
    if(windowWidth > 800) {
        var timer;
        NavigationArrow();      
        $('#main-nav > li').hover(function(){
            clearTimeout(timer);
            NavigationArrow($(this));
        }, function(){
            timer = setTimeout(function(){
                NavigationArrow();
            }, 300);        
        });
        $('#main-nav .menu-item-has-children').hover(function(){
            // $(this).children('.sub-menu').stop().slideToggle(500, 'easeOutBack');    
            $(this).children('.sub-menu').stop().show();    
        });
    } else {
        $('#main-nav a[href=#]').click(function(e){ e.preventDefault(); });
        // $('#main-nav a[href=#contact-us]').click(function(){ $('#main-nav-wrap').slideUp(600, 'easeOutBack'); });
        $('#main-nav a[href=#contact-us]').click(function(){ $('#main-nav-wrap').hide(); });
        $('#main-nav .menu-item-has-children').click(function(){
            // $(this).children('.sub-menu').stop().slideToggle(500, 'easeOutBack');    
            $(this).children('.sub-menu').stop().show();    
        });
    }



#main-nav .sub-menu {
left: 50%;
margin-left: -66px;
}

#main-nav .sub-menu {
-webkit-transition: none !important;
-khtml-transition: none !important;
-moz-transition: none !important;
-ms-transition: none !important;
-o-transition: none !important;
transition: none !important;
list-style: none;
position: absolute;
top: 100%;
left: 0;
display: none;
padding: 0 10px;
margin: 0;
width: 133px;
height: auto;
text-align: center;
font-size: 14px;
-webkit-border-radius: 0 0 6px 6px;
-khtml-border-radius: 0 0 6px 6px;
-moz-border-radius: 0 0 6px 6px;
-ms-border-radius: 0 0 6px 6px;
-o-border-radius: 0 0 6px 6px;
border-radius: 0 0 6px 6px;
background: #fff;
background: rgba(255,255,255,0.95);
}

.sub-menu {
-webkit-box-shadow: 0px 0px 8px 0px rgba(50,50,50,0.25);
-moz-box-shadow: 0px 0px 8px 0px rgba(50,50,50,0.25);
box-shadow: 0px 0px 8px 0px rgba(50,50,50,0.25);
}