Html Mozilla Firefox ESR（最新版本17）不会显示我的站点菜单，适用于所有其他浏览器

我今天遇到了一个奇怪的困境——我的网站菜单在mozilla firefox ESR（17.03+）上根本不会显示

以下是“我的菜单”设置为正常显示的方式：

但当我将其加载到MFESR上时：我收到的是：

下面是我的HTML和CSS代码：

<div class="container">
        <div id="menu_placehold">
            <header class="slide">     <!-- Add "slideRight" class to items that move right when viewing Nav Drawer  -->
                <ul id="navToggle" class="burger slide">    <!--    Add "slideRight" class to items that move right when viewing Nav Drawer  -->
                    <li></li><li></li><li></li>
                </ul>
                <div class="cf"></div>
                <a href="index.html"><img src="img/logo/menu_logo.png" class="header_icon" /><h1>Vogel</h1></a>
                <div class="cf"></div>
            </header>

            <nav class="slide">
                <ul>
                    <li><a href="index.html">HOME</a></li>
                    <li><a href="solar.html" class="active">SOLAR</a></li>
                    <li><a href="electrical.html">ELECTRICAL</a></li>
                    <li><a href="about.html">ABOUT</a></li>
                    <li><a href="team.html">TEAM</a></li>
                    <li><a href="contact.html">CONTACT</a></li>
                    <li><a href="blog/">BLOG</a></li>
                </ul>   
                <div class="socials socials_fix">
                    <div class="social_icos">
                        <a href="#"><img src="img/assets/icons/linkedin.png" style="width:30px; height: 30px;"/></a>
                        <a href="#"><img src="img/assets/icons/google_plus.png" style="width:30px; height: 30px;"/></a>
                        <a href="#"><img src="img/assets/icons/facebook.png" style="width:30px; height: 30px;"/></a>
                        <a href="#"><img src="img/assets/icons/twitter.png" style="width:30px; height: 30px;"/></a>
                        <a href="#"><img src="img/assets/icons/instagram.png" style="width:30px; height: 30px;"/></a>
                        <a href="#"><img src="img/assets/icons/youtube.png" style="width:30px; height: 30px;"/></a>
                    </div>
                </div>
            </nav>

            <div class="menu_number"><a href="callto:#"><h1>PHONENUMBERHERE</h1></a></div>

        </div>
    </div>

---

编辑：我相信这与backface visibility设置为hidden有关，当我在element inspection屏幕中禁用它时，菜单显示，但是当我对css进行任何更改时，它仍然保持隐藏状态。

我发现Mozilla Firefox ESR与backface visibility:hidden有一个非常奇怪的交互作用（-moz背面可视性）。当将具有固定位置的元素放置在背面可见性设置为“隐藏”的另一个元素上时，该元素似乎会忽略任何z索引placehold。我将容器设置为“-moz backface visibility:visible；”现在它显示出来了，非常非常奇怪。它在firefox的标准发行版上运行良好

body {
    background-color: #000;
    color: #9aa6af;
    text-rendering: optimizelegibility;

    -webkit-tap-highlight-color:rgba(0,0,0,0);
    -webkit-text-size-adjust: none;
    -webkit-font-smoothing: antialiased;

    -moz-tap-highlight-color:rgba(0,0,0,0); 
    -moz-text-size-adjust: none;
    -moz-font-smoothing: antialiased;

    -ms-tap-highlight-color:rgba(0,0,0,0); 
    -ms-text-size-adjust: none;
    -ms-font-smoothing: antialiased;
}
a {text-decoration: none;}

#list li {
color: #89c441;
}

.text_green {font-weight:700;}
.container {overflow: hidden; background-color: #000;


/*  Prevents Flickering  */
    -webkit-backface-visibility: hidden;
    -moz-backface-visibility: hidden;
    -ms-backface-visibility: hidden;
}

/*=== fiddling ===*/


header {
    height: 60px;
    z-index: 2;
    background-color: #404040;

    position: fixed;
    top: 0;
    right: 0;
    left: 0;


}
header h1 {
    color: #fff;
    text-align: left;
    font-size: 27px;
    line-height: 60px;
    font-weight: bold;
    padding-left: 20px;
}

.burger {
    position: absolute;
    float: left;
    padding: 10px;
    top: 4px;
    left: 10px;
    list-style: none;
    display: none;
}
.burger li {
    width: 30px;
    height: 4px;
    background-color: #fff;
    border-radius: 3px;
    margin: 5px 0;
}
.burger.open li {background-color: #d9dde1;}

nav {
    position: fixed;
    z-index:3;
    top: 0;
    right: calc(50% - 450px);
    right: -webkit-calc(50% - 450px);
    right: -moz-calc(50% - 450px);
    right: -o-calc(50% - 450px);
    width: 850px;

}
nav li {
    float: left;

    display: inline-block;
}
nav li a {
    font-size: 15px;
    color: #fff;
    padding: 20px 15px;
    font-weight: 700;
    display: block;
}
nav li a:hover {color: #89c441;}
@media only screen and (max-width: 1400px) {
nav {width: 750px;}
}


@media only screen and (max-width: 950px) {
.socials {display:none;}
nav {width:600px; right: 5px;}
}

@media only screen and (max-width: 800px) {
.main_body{padding-top: 0;}
header {
    height: 60px;
    z-index: 2;
    background-color: #404040;

    position: fixed;
    top: 0;
    right: 0;
    left: 0;

        /* starting point */
    -webkit-transform: translate3d(0,0,0);
    -moz-transform: translate3d(0,0,0);
    transform: translate3d(0,0,0);
}
header h1 {
    color: #ffffff;
    text-align: center;
    padding-left: 0;
    display: block;
    float:left;
}
.burger {display: block;}


/*  Nav Drawer Layout  */
nav {position: relative;}

nav ul {
    height: 100%;
    overflow-y: auto;
}
nav li {
    display: block;
    float: none;
}
nav li a {
    padding: 22px 25px;
    letter-spacing: 3px;
    font-size: 14px;
}
nav li a.logo {
    display: none;
}
nav li a.active {
    color: #89c441;
    background-color: #5D5D5D;
}
nav li a:hover {
    color: #fff;
    background-color: #404040;
}
nav li:first-child a.active,
nav li:first-child a:hover 
{border-radius: 10px 0 0 0;}

.header-section {margin-top: 60px;}


/* NAVIGATION ANNIMATION */
nav {
    width: 93%;

    position: fixed;
    left: 0;
    top: 0;
    margin: 0;
    background-color: #5D5D5D;
    border-radius: 8px;
    z-index:-20;
    /* starting point */
    opacity: .3;
    -webkit-transform: translate3d(5%,0,0)scale(.97);
    -moz-transform: translate3d(5%,0,0)scale(.97);
    transform: translate3d(5%,0,0)scale(.97);
}

/*Nav Expanding Open Effect*/
nav.open {
    opacity: 1;

    -webkit-transform: translate3d(0,0,0)scale(1);
    -webkit-animation: slideIn .35s ease-in-out;

    -moz-transform: translate3d(0,0,0)scale(1);
    -moz-animation: slideIn .35s ease-in-out;

    transform: translate3d(0,0,0)scale(1);
    animation: slideIn .35s ease-in-out;
    z-index:1;
}
@-webkit-keyframes slideIn {
    0%       {opacity: .3;
                -webkit-transform: translate3d(5%,0,0)scale(.97);}
    100%  {opacity: 1;
                -webkit-transform: translate3d(0,0,0)scale(1);}
}
@-moz-keyframes slideIn {
    0%      {opacity: .3;
                -moz-transform: translate3d(5%,0,0)scale(.97);}
    100%  {opacity: 1;
                -moz-transform: translate3d(0,0,0)scale(1);}
}
@keyframes slideIn {
    0%      {opacity: .3;
                transform: translate3d(5%,0,0)scale(.97);}
    100%  {opacity: 1;
                transform: translate3d(0,0,0)scale(1);}
}

/*Nav Shrinking Closed Effect*/
nav.close {
    opacity: .3;

    -webkit-transform: translate3d(5%,0,0)scale(.97);
    -webkit-animation: slideOut .3s ease-in-out;

    -moz-transform: translate3d(5%,0,0)scale(.97);
    -moz-animation: slideOut .3s ease-in-out;

    transform: translate3d(5%,0,0)scale(.97);
    animation: slideOut .3s ease-in-out;
}
@-webkit-keyframes slideOut {
    0%      {opacity: 1;
                -webkit-transform: translate3d(0,0,0)scale(1);}
    100%  {opacity: .3;
                -webkit-transform: translate3d(5%,0,0)scale(.97);}
}
@-moz-keyframes slideOut {
    0%      {opacity: 1;
                -moz-transform: translate3d(0,0,0)scale(1);}
    100%  {opacity: .3;
                -moz-transform: translate3d(5%,0,0)scale(.97);}
}
@keyframes slideOut {
    0%      {opacity: 1;
                transform: translate3d(0,0,0)scale(1);}
    100%  {opacity: .3;
                transform: translate3d(5%,0,0)scale(.97);}
}



/* CONTENT ANNIMATION */
.content {
    /* starting point */
    -webkit-transform: translate3d(0,0,0);
    -moz-transform: translate3d(0,0,0);
    transform: translate3d(0,0,0);
    z-index: 1;
}

/*Content Sliding Open Effect*/
header.open,
.content.open 
{   
    -webkit-transform: translate3d(240px,0,0);
    -webkit-animation: open .5s ease-in-out;

    -moz-transform: translate3d(240px,0,0);
    -moz-animation: open .5s ease-in-out;

    transform: translate3d(240px,0,0);
    animation: open .5s ease-in-out;
}
@-webkit-keyframes open {
    0%      {-webkit-transform: translate3d(0,0,0);}
    70%    {-webkit-transform: translate3d(260px,0,0);}
    100%  {-webkit-transform: translate3d(240px,0,0);}
}
@-moz-keyframes open {
    0%      {-moz-transform: translate3d(0,0,0);}
    70%    {-moz-transform: translate3d(260px,0,0);}
    100%  {-moz-transform: translate3d(240px,0,0);}
}
@keyframes open {
    0%      {transform: translate3d(0,0,0);}
    70%    {transform: translate3d(260px,0,0);}
    100%  {transform: translate3d(240px,0,0);}
}

/*Content Sliding Closed Effect*/
header.close,
.content.close 
{
    -webkit-transform: translate3d(0,0,0);
    -webkit-animation: close .3s ease-in-out;

    -moz-transform: translate3d(0,0,0);
    -moz-animation: close .3s ease-in-out;

    transform: translate3d(0,0,0);
    animation: close .3s ease-in-out;
}
@-webkit-keyframes close {
    0%      {-webkit-transform: translate3d(240px,0,0);}
    100%  {-webkit-transform: translate3d(0,0,0);}
}
@-moz-keyframes close {
    0%       {-moz-transform: translate3d(240px,0,0);}
    100%  {-moz-transform: translate3d(0,0,0);}
}
@keyframes close {
    0%       {transform: translate3d(240px,0,0);}
    100%  {transform: translate3d(0,0,0);}
}

}