html.de - Menü wird nicht geöffnet

by SpiceLab

HTML

<div class="header">
        <div class="container row">
            <div class="logo">
                <a href="start.html" title="Start">
                     <img id="headlogo" src="STU-LOGO2.png">
                </a>
            </div>
            <ul class="services-list">
                <li class="services list-item">
                    <ul class="navlist">
                        <li class="content-services openmenu">Services <i class="fa fa-angle-down"></i>
                        <ul class="sub-list">
                            <li class="sub-list-item subgroups cell">
                                <a href="groups.html" title="Kurse">
                                    <div class=cellbar>
                                        <i class="fa fa-th fa-3x"></i>
                                        <p class="incelltext groupstext">Kurse</p>
                                    </div>
                                </a>
                            </li>
                            <li class="sub-list-item subchats cell">
                                <a href="messages.html" title="Nachrichten">
                                    <div class=cellbar>
                                        <i class="fa fa-comments fa-3x"></i>
                                        <p class="incelltext groupstext">Nachrichten</p>
                                    </div>
                                </a>
                            </li>
                            <li class="sub-list-item subplans cell">
                                <a href="plans.html" title="Vertretungspläne">
                                    <div class=cellbar>
                                        <i class="fa fa-columns fa-3x"></i>
                                        <p class="incelltext groupstext">Vertretungs- pläne</p>
                                    </div>
                                </a>
                            </li>
                            <li...

CSS

@import url(https://fonts.googleapis.com/css?family=Open+Sans:400,300);
@import url(https://fonts.googleapis.com/css?family=Comfortaa:400,700,300);
@import url(https://fonts.googleapis.com/css?family=Lato:400,700,300);
@import url(https://fonts.googleapis.com/css?family=Source+Sans+Pro:400,300,600,700);
@import url(https://fonts.googleapis.com/css?family=Asap:400,700);
 
/*
*****************************
* 1. COMMON                 *
*****************************
*/
 
body {
    font:14px Open Sans, serif;
    border-top: 3px solid #fff !important;
    text-align: justify;
    line-height: 22px;
}
 
* {
  margin: 0px;
  padding: 0px;
}
 
.row {
    width: 1140px !important;
    margin-left: auto;
    margin-right: auto;
}
 
a {
    text-decoration: none;
}
/*
*****************************
* 2. HEADER                 *
*****************************
*/
.header {
    position: fixed;
    top: 0px;
    width: 100%;
    background-color: #FFF;
    height: 86px;
    border-bottom: 2px solid #EDEDED;
    z-index: 2;
}
 
#headlogo {
    height: auto;
    width: 220px;
    margin-top: 25px;
    float: left;
}
 
.sub-list-holder {
    height: 0px;
    position: absolute;
    margin-top: -15px;
    left: 0px;
    width: 100%;
    background-color: #FFF;
}
 
.sub-list {
    width: 1140px;
    padding: 15px 0px;
    margin: 0px auto;
    max-height: 0px;
    table-layout:fixed;
    display: table;
    position:absolute;
    top:50px;
    left:-700px
}
/*.sub-list, .sub-list-holder {
    overflow: hidden;
    box-sizing: border-box;
}*/
 
.sub-list-item {
    box-sizing: border-box;
    position: relative;
    float: left;
    width: 12.5%;
    padding-bottom: 12.5%;
    height: 142.5px;
}
 
.services-list {
    float: right;
    padding-left: 15px;
    display: table;
    table-layout: fixed;
    position:relative
}
 
.list-item {
    padding: 0px 15px;
    box-sizing: border-box;
    float: left;
    line-height: 86px;
    font-weight: 400;
    color: #2C3239;
    font-size:...