Html 子菜单为'；t在mega菜单中正确显示

我正在实现一个大菜单，其中每个项目都有一个子菜单，当我在每个项目上悬停时，必须显示子菜单，但问题是子菜单没有正确显示，并且位于主UL元素下。 我更改了z索引，但它不起作用。 那么解决方案是什么呢？ 我的代码是：

<div class="left side-menu">
                <div class="sidebar-inner slimscrollleft">
                       <div id="sidebar-menu">
                        <ul>
     <!--start mega menu-->

                                <li  class="has-submenu has_sub">
                                    <a href="javascript:void(0);" class="waves-effect MegaClick" ><i class="md md-layers"></i><span> Components </span><span class="menu-arrow"></span></a>
                                    <ul class="submenu megamenu list-unstyled" >
                                        <li>
                                            <ul>
                                                <li><a href="components-widgets.html">Widgets</a></li>
                                                <li><a href="components-nestable-list.html">Nesteble</a></li>
                                                <li><a href="components-range-sliders.html">Range sliders</a></li>
                                                <li><a href="components-masonry.html">Masonry</a></li>
                                                <li><a href="components-animation.html">Animation</a></li>
                                                <li><a href="components-sweet-alert.html">Sweet Alerts</a></li>
                                                <li><a href="components-treeview.html">Tree view</a></li>
                                                <li><a href="components-tour.html">Tour</a></li>
                                            </ul>
                                        </li>
                                        <li>
                                            <ul>

                                                <li><a href="form-elements.html">General Elements</a></li>


                                                   <li class="has_sub">


                                                        <a href="javascript:void(0);" class="waves-effect"><span>Menu Level 1.1</span>  <span class="menu-arrow"></span></a>
                                                        <ul style="">
                                                            <li><a href="javascript:void(0);"><span>Menu Level 2.1</span></a></li>
                                                            <li><a href="javascript:void(0);"><span>Menu Level 2.2</span></a></li>
                                                            <li><a href="javascript:void(0);"><span>Menu Level 2.3</span></a></li>
                                                        </ul>
                                                </li>


                                                <li><a href="form-validation.html">Form Validation</a></li>
                                                <li><a href="form-pickers.html">Form Pickers</a></li>
                                                <li><a href="form-wizard.html">Form Wizard</a></li>
                                            </ul>
                                        </li>

                                        <li>
                                            <ul>
                                                <li><a href="form-mask.html">Form Masks</a></li>
                                                <li><a href="form-summernote.html">Summernote</a></li>
                                                <li><a href="form-wysiwig.html">Wysiwig Editors</a></li>
                                                <li><a href="form-code-editor.html">Code Editor</a></li>
                                                <li><a href="form-uploads.html">Multiple File Upload</a></li>
                                                <li><a href="form-xeditable.html">X-editable</a></li>
                                                <li><a href="form-image-crop.html">Image Crop</a></li>
                                            </ul>
                                        </li>


                                    </ul>
                                </li>

                                <!--end mega menu-->

    </ul>

                            <div class="clearfix"></div>
                        </div>
                        <div class="clearfix"></div>
                    </div>
                </div>

---

我已经分析了你的代码，我从你的代码中了解到有一个列表“组件”，其中包含其余的元素

如果是，您可以复制以下代码

HTML:

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- jQuery -->
<script src="http://code.jquery.com/jquery-latest.min.js"></script>

<!-- MenuMaker Plugin -->
<script src="https://s3.amazonaws.com/menumaker/menumaker.min.js"></script>

<!-- Icon Library -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css">
<meta charset="UTF-8">
<title>Title of the document</title>
</head>

<body>
<div id="cssmenu">
  <ul>
     <li><a href="#" target="_blank"><i class="fa fa-fw fa-asterisk"></i> Components</a>
        <ul>
           <li><a href="#">Widgets</a></li>
           <li><a href="#">Nesteble</a></li>
           <li><a href="#">Range sliders</a></li>
           <li><a href="#">Masonry</a></li>
           <li><a href="#">Animation</a></li>
           <li><a href="#">Sweet Alerts</a></li>
           <li><a href="#">Tree view</a></li>
           <li><a href="#">Tour</a></li>
           <li><a href="#">General Elements</a>
              <ul>
                 <li><a href="#">Menu Level 1</a>
                    <ul>
                       <li><a href="#">Menu Level 1.1</a></li>
                       <li><a href="#">Menu Level 1.2</a></li>
                       <li><a href="#">Menu Level 1.3</a></li>
                    </ul>
                 </li>
              </ul>
           </li>
           <li><a href="#">Form Validation</a></li>
           <li><a href="#">Form Pickers</a></li>
           <li><a href="#">Form Wizard</a></li>
           <li><a href="#">Form Masks</a></li>
           <li><a href="#">Summernote</a></li>
           <li><a href="#">Wysiwig Editors</a></li>
           <li><a href="#">Code Editor</a></li>
           <li><a href="#">Multiple File Upload</a></li>
           <li><a href="#">X-editable</a></li>
           <li><a href="#">Image Crop</a></li>
        </ul>
     </li>
  </ul>
</div>
</body>

</html>

@import url(https://fonts.googleapis.com/css?family=Montserrat:400,700);
#cssmenu,
#cssmenu ul,
#cssmenu ul li,
#cssmenu ul li a,
#cssmenu #menu-button {
  margin: 0;
  padding: 0;
  border: 0;
  list-style: none;
  line-height: 1;
  display: block;
  position: relative;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
}
#cssmenu:after,
#cssmenu > ul:after {
  content: ".";
  display: block;
  clear: both;
  visibility: hidden;
  line-height: 0;
  height: 0;
}
#cssmenu #menu-button {
  display: none;
}
#cssmenu {
  font-family: Montserrat, sans-serif;
  background: #333333;
}
#cssmenu > ul > li {
  float: left;
}
#cssmenu.align-center > ul {
  font-size: 0;
  text-align: center;
}
#cssmenu.align-center > ul > li {
  display: inline-block;
  float: none;
}
#cssmenu.align-center ul ul {
  text-align: left;
}
#cssmenu.align-right > ul > li {
  float: right;
}
#cssmenu > ul > li > a {
  padding: 17px;
  font-size: 12px;
  letter-spacing: 1px;
  text-decoration: none;
  color: #00c7c7;
  font-weight: 700;
  text-transform: uppercase;
}
#cssmenu > ul > li:hover > a {
  color: #00ffff;
}
#cssmenu > ul > li.has-sub > a {
  padding-right: 30px;
}
#cssmenu > ul > li.has-sub > a:after {
  position: absolute;
  top: 22px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu > ul > li.has-sub > a:before {
  position: absolute;
  top: 19px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu > ul > li.has-sub:hover > a:before {
  top: 23px;
  height: 0;
}
#cssmenu ul ul {
  position: absolute;
  left: -9999px;
}
#cssmenu.align-right ul ul {
  text-align: right;
}
#cssmenu ul ul li {
  height: 0;
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu li:hover > ul {
  left: auto;
}
#cssmenu.align-right li:hover > ul {
  left: auto;
  right: 0;
}
#cssmenu li:hover > ul > li {
  height: 35px;
}
#cssmenu ul ul ul {
  margin-left: 100%;
  top: 0;
}
#cssmenu.align-right ul ul ul {
  margin-left: 0;
  margin-right: 100%;
}
#cssmenu ul ul li a {
  border-bottom: 1px solid rgba(150, 150, 150, 0.15);
  padding: 11px 15px;
  width: 170px;
  font-size: 12px;
  text-decoration: none;
  color: #00c7c7;
  font-weight: 400;
  background: #333333;
}
#cssmenu ul ul li:last-child > a,
#cssmenu ul ul li.last-item > a {
  border-bottom: 0;
}
#cssmenu ul ul li:hover > a,
#cssmenu ul ul li a:hover {
  color: #00ffff;
}
#cssmenu ul ul li.has-sub > a:after {
  position: absolute;
  top: 16px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu.align-right ul ul li.has-sub > a:after {
  right: auto;
  left: 11px;
}
#cssmenu ul ul li.has-sub > a:before {
  position: absolute;
  top: 13px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu.align-right ul ul li.has-sub > a:before {
  right: auto;
  left: 14px;
}
#cssmenu ul ul > li.has-sub:hover > a:before {
  top: 17px;
  height: 0;
}
#cssmenu.small-screen {
  width: 100%;
}
#cssmenu.small-screen ul {
  width: 100%;
  display: none;
}
#cssmenu.small-screen.align-center > ul {
  text-align: left;
}
#cssmenu.small-screen ul li {
  width: 100%;
  border-top: 1px solid rgba(120, 120, 120, 0.2);
}
#cssmenu.small-screen ul ul li,
#cssmenu.small-screen li:hover > ul > li {
  height: auto;
}
#cssmenu.small-screen ul li a,
#cssmenu.small-screen ul ul li a {
  width: 100%;
  border-bottom: 0;
}
#cssmenu.small-screen > ul > li {
  float: none;
}
#cssmenu.small-screen ul ul li a {
  padding-left: 25px;
}
#cssmenu.small-screen ul ul ul li a {
  padding-left: 35px;
}
#cssmenu.small-screen ul ul li a {
  color: #00c7c7;
  background: none;
}
#cssmenu.small-screen ul ul li:hover > a,
#cssmenu.small-screen ul ul li.active > a {
  color: #00ffff;
}
#cssmenu.small-screen ul ul,
#cssmenu.small-screen ul ul ul,
#cssmenu.small-screen.align-right ul ul {
  position: relative;
  left: 0;
  width: 100%;
  margin: 0;
  text-align: left;
}
#cssmenu.small-screen > ul > li.has-sub > a:after,
#cssmenu.small-screen > ul > li.has-sub > a:before,
#cssmenu.small-screen ul ul > li.has-sub > a:after,
#cssmenu.small-screen ul ul > li.has-sub > a:before {
  display: none;
}
#cssmenu.small-screen #menu-button {
  display: block;
  padding: 17px;
  color: #00c7c7;
  cursor: pointer;
  font-size: 12px;
  text-transform: uppercase;
  font-weight: 700;
}
#cssmenu.small-screen #menu-button:after {
  position: absolute;
  top: 22px;
  right: 17px;
  display: block;
  height: 4px;
  width: 20px;
  border-top: 2px solid #00c7c7;
  border-bottom: 2px solid #00c7c7;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button:before {
  position: absolute;
  top: 16px;
  right: 17px;
  display: block;
  height: 2px;
  width: 20px;
  background: #00c7c7;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button.menu-opened:after {
  top: 23px;
  border: 0;
  height: 2px;
  width: 15px;
  background: #00ffff;
  -webkit-transform: rotate(45deg);
  -moz-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  transform: rotate(45deg);
}
#cssmenu.small-screen #menu-button.menu-opened:before {
  top: 23px;
  background: #00ffff;
  width: 15px;
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -ms-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
}
#cssmenu.small-screen .submenu-button {
  position: absolute;
  z-index: 99;
  right: 0;
  top: 0;
  display: block;
  border-left: 1px solid rgba(120, 120, 120, 0.2);
  height: 46px;
  width: 46px;
  cursor: pointer;
}
#cssmenu.small-screen .submenu-button.submenu-opened {
  background: #262626;
}
#cssmenu.small-screen ul ul .submenu-button {
  height: 34px;
  width: 34px;
}
#cssmenu.small-screen .submenu-button:after {
  position: absolute;
  top: 22px;
  right: 19px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:after {
  top: 15px;
  right: 13px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:after {
  background: #00ffff;
}
#cssmenu.small-screen .submenu-button:before {
  position: absolute;
  top: 19px;
  right: 22px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:before {
  top: 12px;
  right: 16px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:before {
  display: none;
}
#cssmenu.small-screen.select-list {
  padding: 5px;
}

$("#cssmenu").menumaker({
    title: "Menu",
    breakpoint: 768,
    format: "multitoggle"
});

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- jQuery -->
<script src="http://code.jquery.com/jquery-latest.min.js"></script>

<!-- MenuMaker Plugin -->
<script src="https://s3.amazonaws.com/menumaker/menumaker.min.js"></script>

<!-- Icon Library -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css">
<meta charset="UTF-8">
<title>Title</title>
</head>

<body>
<div id="cssmenu">
  <ul>
     <li><a href="#" target="_blank"><i class="fa fa-fw fa-asterisk"></i> Components</a>
        <ul>
           <li><a href="#">Widgets</a></li>
           <li><a href="#">Nesteble</a></li>
           <li><a href="#">Range sliders</a></li>
           <li><a href="#">Masonry</a></li>
           <li><a href="#">Animation</a></li>
           <li><a href="#">Sweet Alerts</a></li>
           <li><a href="#">Tree view</a></li>
           <li><a href="#">Tour</a></li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-bars"></i> General Elements</a>
        <ul>
           <li><a href="#">Menu Level 1</a>
              <ul>
                 <li><a href="#">Menu Level 1.1</a></li>
                 <li><a href="#">Menu Level 1.2</a></li>
                 <li><a href="#">Menu Level 1.3</a></li>
              </ul>
           </li>
           <li><a href="#">Menu Level 2</a>
              <ul>
                 <li><a href="#">Menu Level 2.1</a>
                    <ul>
                       <li><a href="#">Menu Level 2.1.1</a></li>
                       <li><a href="#">Menu Level 2.1.2</a></li>
                       <li><a href="#">Menu Level 2.1.3</a></li>
                    </ul>
                 </li>
                 <li><a href="#">Menu Level 2.2</a></li>
                 <li><a href="#">Menu Level 2.3</a></li>
                 <li><a href="#">Menu Level 2.4</a></li>
              </ul>
           </li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-circle-o-notch"></i> Forms</a>
        <ul>
           <li><a href="#">Form Validation</a></li>
           <li><a href="#">Form Pickers</a></li>
           <li><a href="#">Form Wizard</a></li>
           <li><a href="#">Form Masks</a></li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-check"></i> Services</a>
        <ul>
           <li><a href="#">Summernote</a></li>
           <li><a href="#">Wysiwig Editors</a></li>
           <li><a href="#">Code Editor</a></li>
           <li><a href="#">Multiple File Upload</a></li>
           <li><a href="#">X-editable</a></li>
           <li><a href="#">Image Crop</a></li>
        </ul>
     </li>
  </ul>
</div>
</body>

</html>

@import url(https://fonts.googleapis.com/css?family=Montserrat:400,700);
#cssmenu,
#cssmenu ul,
#cssmenu ul li,
#cssmenu ul li a,
#cssmenu #menu-button {
  margin: 0;
  padding: 0;
  border: 0;
  list-style: none;
  line-height: 1;
  display: block;
  position: relative;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
}
#cssmenu:after,
#cssmenu > ul:after {
  content: ".";
  display: block;
  clear: both;
  visibility: hidden;
  line-height: 0;
  height: 0;
}
#cssmenu #menu-button {
  display: none;
}
#cssmenu {
  font-family: Montserrat, sans-serif;
  background: #333333;
}
#cssmenu > ul > li {
  float: left;
}
#cssmenu.align-center > ul {
  font-size: 0;
  text-align: center;
}
#cssmenu.align-center > ul > li {
  display: inline-block;
  float: none;
}
#cssmenu.align-center ul ul {
  text-align: left;
}
#cssmenu.align-right > ul > li {
  float: right;
}
#cssmenu > ul > li > a {
  padding: 17px;
  font-size: 12px;
  letter-spacing: 1px;
  text-decoration: none;
  color: #f68181;
  font-weight: 700;
  text-transform: uppercase;
}
#cssmenu > ul > li:hover > a {
  color: #ff0000;
}
#cssmenu > ul > li.has-sub > a {
  padding-right: 30px;
}
#cssmenu > ul > li.has-sub > a:after {
  position: absolute;
  top: 22px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu > ul > li.has-sub > a:before {
  position: absolute;
  top: 19px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu > ul > li.has-sub:hover > a:before {
  top: 23px;
  height: 0;
}
#cssmenu ul ul {
  position: absolute;
  left: -9999px;
}
#cssmenu.align-right ul ul {
  text-align: right;
}
#cssmenu ul ul li {
  height: 0;
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu li:hover > ul {
  left: auto;
}
#cssmenu.align-right li:hover > ul {
  left: auto;
  right: 0;
}
#cssmenu li:hover > ul > li {
  height: 35px;
}
#cssmenu ul ul ul {
  margin-left: 100%;
  top: 0;
}
#cssmenu.align-right ul ul ul {
  margin-left: 0;
  margin-right: 100%;
}
#cssmenu ul ul li a {
  border-bottom: 1px solid rgba(150, 150, 150, 0.15);
  padding: 11px 15px;
  width: 170px;
  font-size: 12px;
  text-decoration: none;
  color: #f68181;
  font-weight: 400;
  background: #333333;
}
#cssmenu ul ul li:last-child > a,
#cssmenu ul ul li.last-item > a {
  border-bottom: 0;
}
#cssmenu ul ul li:hover > a,
#cssmenu ul ul li a:hover {
  color: #ff0000;
}
#cssmenu ul ul li.has-sub > a:after {
  position: absolute;
  top: 16px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu.align-right ul ul li.has-sub > a:after {
  right: auto;
  left: 11px;
}
#cssmenu ul ul li.has-sub > a:before {
  position: absolute;
  top: 13px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu.align-right ul ul li.has-sub > a:before {
  right: auto;
  left: 14px;
}
#cssmenu ul ul > li.has-sub:hover > a:before {
  top: 17px;
  height: 0;
}
#cssmenu.small-screen {
  width: 100%;
}
#cssmenu.small-screen ul {
  width: 100%;
  display: none;
}
#cssmenu.small-screen.align-center > ul {
  text-align: left;
}
#cssmenu.small-screen ul li {
  width: 100%;
  border-top: 1px solid rgba(120, 120, 120, 0.2);
}
#cssmenu.small-screen ul ul li,
#cssmenu.small-screen li:hover > ul > li {
  height: auto;
}
#cssmenu.small-screen ul li a,
#cssmenu.small-screen ul ul li a {
  width: 100%;
  border-bottom: 0;
}
#cssmenu.small-screen > ul > li {
  float: none;
}
#cssmenu.small-screen ul ul li a {
  padding-left: 25px;
}
#cssmenu.small-screen ul ul ul li a {
  padding-left: 35px;
}
#cssmenu.small-screen ul ul li a {
  color: #f68181;
  background: none;
}
#cssmenu.small-screen ul ul li:hover > a,
#cssmenu.small-screen ul ul li.active > a {
  color: #ff0000;
}
#cssmenu.small-screen ul ul,
#cssmenu.small-screen ul ul ul,
#cssmenu.small-screen.align-right ul ul {
  position: relative;
  left: 0;
  width: 100%;
  margin: 0;
  text-align: left;
}
#cssmenu.small-screen > ul > li.has-sub > a:after,
#cssmenu.small-screen > ul > li.has-sub > a:before,
#cssmenu.small-screen ul ul > li.has-sub > a:after,
#cssmenu.small-screen ul ul > li.has-sub > a:before {
  display: none;
}
#cssmenu.small-screen #menu-button {
  display: block;
  padding: 17px;
  color: #f68181;
  cursor: pointer;
  font-size: 12px;
  text-transform: uppercase;
  font-weight: 700;
}
#cssmenu.small-screen #menu-button:after {
  position: absolute;
  top: 22px;
  right: 17px;
  display: block;
  height: 4px;
  width: 20px;
  border-top: 2px solid #f68181;
  border-bottom: 2px solid #f68181;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button:before {
  position: absolute;
  top: 16px;
  right: 17px;
  display: block;
  height: 2px;
  width: 20px;
  background: #f68181;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button.menu-opened:after {
  top: 23px;
  border: 0;
  height: 2px;
  width: 15px;
  background: #ff0000;
  -webkit-transform: rotate(45deg);
  -moz-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  transform: rotate(45deg);
}
#cssmenu.small-screen #menu-button.menu-opened:before {
  top: 23px;
  background: #ff0000;
  width: 15px;
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -ms-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
}
#cssmenu.small-screen .submenu-button {
  position: absolute;
  z-index: 99;
  right: 0;
  top: 0;
  display: block;
  border-left: 1px solid rgba(120, 120, 120, 0.2);
  height: 46px;
  width: 46px;
  cursor: pointer;
}
#cssmenu.small-screen .submenu-button.submenu-opened {
  background: #262626;
}
#cssmenu.small-screen ul ul .submenu-button {
  height: 34px;
  width: 34px;
}
#cssmenu.small-screen .submenu-button:after {
  position: absolute;
  top: 22px;
  right: 19px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:after {
  top: 15px;
  right: 13px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:after {
  background: #ff0000;
}
#cssmenu.small-screen .submenu-button:before {
  position: absolute;
  top: 19px;
  right: 22px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:before {
  top: 12px;
  right: 16px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:before {
  display: none;
}
#cssmenu.small-screen.select-list {
  padding: 5px;
}

$("#cssmenu").menumaker({
    title: "Menu",
    breakpoint: 768,
    format: "multitoggle"
});

Javascript:

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- jQuery -->
<script src="http://code.jquery.com/jquery-latest.min.js"></script>

<!-- MenuMaker Plugin -->
<script src="https://s3.amazonaws.com/menumaker/menumaker.min.js"></script>

<!-- Icon Library -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css">
<meta charset="UTF-8">
<title>Title of the document</title>
</head>

<body>
<div id="cssmenu">
  <ul>
     <li><a href="#" target="_blank"><i class="fa fa-fw fa-asterisk"></i> Components</a>
        <ul>
           <li><a href="#">Widgets</a></li>
           <li><a href="#">Nesteble</a></li>
           <li><a href="#">Range sliders</a></li>
           <li><a href="#">Masonry</a></li>
           <li><a href="#">Animation</a></li>
           <li><a href="#">Sweet Alerts</a></li>
           <li><a href="#">Tree view</a></li>
           <li><a href="#">Tour</a></li>
           <li><a href="#">General Elements</a>
              <ul>
                 <li><a href="#">Menu Level 1</a>
                    <ul>
                       <li><a href="#">Menu Level 1.1</a></li>
                       <li><a href="#">Menu Level 1.2</a></li>
                       <li><a href="#">Menu Level 1.3</a></li>
                    </ul>
                 </li>
              </ul>
           </li>
           <li><a href="#">Form Validation</a></li>
           <li><a href="#">Form Pickers</a></li>
           <li><a href="#">Form Wizard</a></li>
           <li><a href="#">Form Masks</a></li>
           <li><a href="#">Summernote</a></li>
           <li><a href="#">Wysiwig Editors</a></li>
           <li><a href="#">Code Editor</a></li>
           <li><a href="#">Multiple File Upload</a></li>
           <li><a href="#">X-editable</a></li>
           <li><a href="#">Image Crop</a></li>
        </ul>
     </li>
  </ul>
</div>
</body>

</html>

@import url(https://fonts.googleapis.com/css?family=Montserrat:400,700);
#cssmenu,
#cssmenu ul,
#cssmenu ul li,
#cssmenu ul li a,
#cssmenu #menu-button {
  margin: 0;
  padding: 0;
  border: 0;
  list-style: none;
  line-height: 1;
  display: block;
  position: relative;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
}
#cssmenu:after,
#cssmenu > ul:after {
  content: ".";
  display: block;
  clear: both;
  visibility: hidden;
  line-height: 0;
  height: 0;
}
#cssmenu #menu-button {
  display: none;
}
#cssmenu {
  font-family: Montserrat, sans-serif;
  background: #333333;
}
#cssmenu > ul > li {
  float: left;
}
#cssmenu.align-center > ul {
  font-size: 0;
  text-align: center;
}
#cssmenu.align-center > ul > li {
  display: inline-block;
  float: none;
}
#cssmenu.align-center ul ul {
  text-align: left;
}
#cssmenu.align-right > ul > li {
  float: right;
}
#cssmenu > ul > li > a {
  padding: 17px;
  font-size: 12px;
  letter-spacing: 1px;
  text-decoration: none;
  color: #00c7c7;
  font-weight: 700;
  text-transform: uppercase;
}
#cssmenu > ul > li:hover > a {
  color: #00ffff;
}
#cssmenu > ul > li.has-sub > a {
  padding-right: 30px;
}
#cssmenu > ul > li.has-sub > a:after {
  position: absolute;
  top: 22px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu > ul > li.has-sub > a:before {
  position: absolute;
  top: 19px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu > ul > li.has-sub:hover > a:before {
  top: 23px;
  height: 0;
}
#cssmenu ul ul {
  position: absolute;
  left: -9999px;
}
#cssmenu.align-right ul ul {
  text-align: right;
}
#cssmenu ul ul li {
  height: 0;
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu li:hover > ul {
  left: auto;
}
#cssmenu.align-right li:hover > ul {
  left: auto;
  right: 0;
}
#cssmenu li:hover > ul > li {
  height: 35px;
}
#cssmenu ul ul ul {
  margin-left: 100%;
  top: 0;
}
#cssmenu.align-right ul ul ul {
  margin-left: 0;
  margin-right: 100%;
}
#cssmenu ul ul li a {
  border-bottom: 1px solid rgba(150, 150, 150, 0.15);
  padding: 11px 15px;
  width: 170px;
  font-size: 12px;
  text-decoration: none;
  color: #00c7c7;
  font-weight: 400;
  background: #333333;
}
#cssmenu ul ul li:last-child > a,
#cssmenu ul ul li.last-item > a {
  border-bottom: 0;
}
#cssmenu ul ul li:hover > a,
#cssmenu ul ul li a:hover {
  color: #00ffff;
}
#cssmenu ul ul li.has-sub > a:after {
  position: absolute;
  top: 16px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu.align-right ul ul li.has-sub > a:after {
  right: auto;
  left: 11px;
}
#cssmenu ul ul li.has-sub > a:before {
  position: absolute;
  top: 13px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu.align-right ul ul li.has-sub > a:before {
  right: auto;
  left: 14px;
}
#cssmenu ul ul > li.has-sub:hover > a:before {
  top: 17px;
  height: 0;
}
#cssmenu.small-screen {
  width: 100%;
}
#cssmenu.small-screen ul {
  width: 100%;
  display: none;
}
#cssmenu.small-screen.align-center > ul {
  text-align: left;
}
#cssmenu.small-screen ul li {
  width: 100%;
  border-top: 1px solid rgba(120, 120, 120, 0.2);
}
#cssmenu.small-screen ul ul li,
#cssmenu.small-screen li:hover > ul > li {
  height: auto;
}
#cssmenu.small-screen ul li a,
#cssmenu.small-screen ul ul li a {
  width: 100%;
  border-bottom: 0;
}
#cssmenu.small-screen > ul > li {
  float: none;
}
#cssmenu.small-screen ul ul li a {
  padding-left: 25px;
}
#cssmenu.small-screen ul ul ul li a {
  padding-left: 35px;
}
#cssmenu.small-screen ul ul li a {
  color: #00c7c7;
  background: none;
}
#cssmenu.small-screen ul ul li:hover > a,
#cssmenu.small-screen ul ul li.active > a {
  color: #00ffff;
}
#cssmenu.small-screen ul ul,
#cssmenu.small-screen ul ul ul,
#cssmenu.small-screen.align-right ul ul {
  position: relative;
  left: 0;
  width: 100%;
  margin: 0;
  text-align: left;
}
#cssmenu.small-screen > ul > li.has-sub > a:after,
#cssmenu.small-screen > ul > li.has-sub > a:before,
#cssmenu.small-screen ul ul > li.has-sub > a:after,
#cssmenu.small-screen ul ul > li.has-sub > a:before {
  display: none;
}
#cssmenu.small-screen #menu-button {
  display: block;
  padding: 17px;
  color: #00c7c7;
  cursor: pointer;
  font-size: 12px;
  text-transform: uppercase;
  font-weight: 700;
}
#cssmenu.small-screen #menu-button:after {
  position: absolute;
  top: 22px;
  right: 17px;
  display: block;
  height: 4px;
  width: 20px;
  border-top: 2px solid #00c7c7;
  border-bottom: 2px solid #00c7c7;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button:before {
  position: absolute;
  top: 16px;
  right: 17px;
  display: block;
  height: 2px;
  width: 20px;
  background: #00c7c7;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button.menu-opened:after {
  top: 23px;
  border: 0;
  height: 2px;
  width: 15px;
  background: #00ffff;
  -webkit-transform: rotate(45deg);
  -moz-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  transform: rotate(45deg);
}
#cssmenu.small-screen #menu-button.menu-opened:before {
  top: 23px;
  background: #00ffff;
  width: 15px;
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -ms-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
}
#cssmenu.small-screen .submenu-button {
  position: absolute;
  z-index: 99;
  right: 0;
  top: 0;
  display: block;
  border-left: 1px solid rgba(120, 120, 120, 0.2);
  height: 46px;
  width: 46px;
  cursor: pointer;
}
#cssmenu.small-screen .submenu-button.submenu-opened {
  background: #262626;
}
#cssmenu.small-screen ul ul .submenu-button {
  height: 34px;
  width: 34px;
}
#cssmenu.small-screen .submenu-button:after {
  position: absolute;
  top: 22px;
  right: 19px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:after {
  top: 15px;
  right: 13px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:after {
  background: #00ffff;
}
#cssmenu.small-screen .submenu-button:before {
  position: absolute;
  top: 19px;
  right: 22px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:before {
  top: 12px;
  right: 16px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:before {
  display: none;
}
#cssmenu.small-screen.select-list {
  padding: 5px;
}

$("#cssmenu").menumaker({
    title: "Menu",
    breakpoint: 768,
    format: "multitoggle"
});

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- jQuery -->
<script src="http://code.jquery.com/jquery-latest.min.js"></script>

<!-- MenuMaker Plugin -->
<script src="https://s3.amazonaws.com/menumaker/menumaker.min.js"></script>

<!-- Icon Library -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css">
<meta charset="UTF-8">
<title>Title</title>
</head>

<body>
<div id="cssmenu">
  <ul>
     <li><a href="#" target="_blank"><i class="fa fa-fw fa-asterisk"></i> Components</a>
        <ul>
           <li><a href="#">Widgets</a></li>
           <li><a href="#">Nesteble</a></li>
           <li><a href="#">Range sliders</a></li>
           <li><a href="#">Masonry</a></li>
           <li><a href="#">Animation</a></li>
           <li><a href="#">Sweet Alerts</a></li>
           <li><a href="#">Tree view</a></li>
           <li><a href="#">Tour</a></li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-bars"></i> General Elements</a>
        <ul>
           <li><a href="#">Menu Level 1</a>
              <ul>
                 <li><a href="#">Menu Level 1.1</a></li>
                 <li><a href="#">Menu Level 1.2</a></li>
                 <li><a href="#">Menu Level 1.3</a></li>
              </ul>
           </li>
           <li><a href="#">Menu Level 2</a>
              <ul>
                 <li><a href="#">Menu Level 2.1</a>
                    <ul>
                       <li><a href="#">Menu Level 2.1.1</a></li>
                       <li><a href="#">Menu Level 2.1.2</a></li>
                       <li><a href="#">Menu Level 2.1.3</a></li>
                    </ul>
                 </li>
                 <li><a href="#">Menu Level 2.2</a></li>
                 <li><a href="#">Menu Level 2.3</a></li>
                 <li><a href="#">Menu Level 2.4</a></li>
              </ul>
           </li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-circle-o-notch"></i> Forms</a>
        <ul>
           <li><a href="#">Form Validation</a></li>
           <li><a href="#">Form Pickers</a></li>
           <li><a href="#">Form Wizard</a></li>
           <li><a href="#">Form Masks</a></li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-check"></i> Services</a>
        <ul>
           <li><a href="#">Summernote</a></li>
           <li><a href="#">Wysiwig Editors</a></li>
           <li><a href="#">Code Editor</a></li>
           <li><a href="#">Multiple File Upload</a></li>
           <li><a href="#">X-editable</a></li>
           <li><a href="#">Image Crop</a></li>
        </ul>
     </li>
  </ul>
</div>
</body>

</html>

@import url(https://fonts.googleapis.com/css?family=Montserrat:400,700);
#cssmenu,
#cssmenu ul,
#cssmenu ul li,
#cssmenu ul li a,
#cssmenu #menu-button {
  margin: 0;
  padding: 0;
  border: 0;
  list-style: none;
  line-height: 1;
  display: block;
  position: relative;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
}
#cssmenu:after,
#cssmenu > ul:after {
  content: ".";
  display: block;
  clear: both;
  visibility: hidden;
  line-height: 0;
  height: 0;
}
#cssmenu #menu-button {
  display: none;
}
#cssmenu {
  font-family: Montserrat, sans-serif;
  background: #333333;
}
#cssmenu > ul > li {
  float: left;
}
#cssmenu.align-center > ul {
  font-size: 0;
  text-align: center;
}
#cssmenu.align-center > ul > li {
  display: inline-block;
  float: none;
}
#cssmenu.align-center ul ul {
  text-align: left;
}
#cssmenu.align-right > ul > li {
  float: right;
}
#cssmenu > ul > li > a {
  padding: 17px;
  font-size: 12px;
  letter-spacing: 1px;
  text-decoration: none;
  color: #f68181;
  font-weight: 700;
  text-transform: uppercase;
}
#cssmenu > ul > li:hover > a {
  color: #ff0000;
}
#cssmenu > ul > li.has-sub > a {
  padding-right: 30px;
}
#cssmenu > ul > li.has-sub > a:after {
  position: absolute;
  top: 22px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu > ul > li.has-sub > a:before {
  position: absolute;
  top: 19px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu > ul > li.has-sub:hover > a:before {
  top: 23px;
  height: 0;
}
#cssmenu ul ul {
  position: absolute;
  left: -9999px;
}
#cssmenu.align-right ul ul {
  text-align: right;
}
#cssmenu ul ul li {
  height: 0;
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu li:hover > ul {
  left: auto;
}
#cssmenu.align-right li:hover > ul {
  left: auto;
  right: 0;
}
#cssmenu li:hover > ul > li {
  height: 35px;
}
#cssmenu ul ul ul {
  margin-left: 100%;
  top: 0;
}
#cssmenu.align-right ul ul ul {
  margin-left: 0;
  margin-right: 100%;
}
#cssmenu ul ul li a {
  border-bottom: 1px solid rgba(150, 150, 150, 0.15);
  padding: 11px 15px;
  width: 170px;
  font-size: 12px;
  text-decoration: none;
  color: #f68181;
  font-weight: 400;
  background: #333333;
}
#cssmenu ul ul li:last-child > a,
#cssmenu ul ul li.last-item > a {
  border-bottom: 0;
}
#cssmenu ul ul li:hover > a,
#cssmenu ul ul li a:hover {
  color: #ff0000;
}
#cssmenu ul ul li.has-sub > a:after {
  position: absolute;
  top: 16px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu.align-right ul ul li.has-sub > a:after {
  right: auto;
  left: 11px;
}
#cssmenu ul ul li.has-sub > a:before {
  position: absolute;
  top: 13px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu.align-right ul ul li.has-sub > a:before {
  right: auto;
  left: 14px;
}
#cssmenu ul ul > li.has-sub:hover > a:before {
  top: 17px;
  height: 0;
}
#cssmenu.small-screen {
  width: 100%;
}
#cssmenu.small-screen ul {
  width: 100%;
  display: none;
}
#cssmenu.small-screen.align-center > ul {
  text-align: left;
}
#cssmenu.small-screen ul li {
  width: 100%;
  border-top: 1px solid rgba(120, 120, 120, 0.2);
}
#cssmenu.small-screen ul ul li,
#cssmenu.small-screen li:hover > ul > li {
  height: auto;
}
#cssmenu.small-screen ul li a,
#cssmenu.small-screen ul ul li a {
  width: 100%;
  border-bottom: 0;
}
#cssmenu.small-screen > ul > li {
  float: none;
}
#cssmenu.small-screen ul ul li a {
  padding-left: 25px;
}
#cssmenu.small-screen ul ul ul li a {
  padding-left: 35px;
}
#cssmenu.small-screen ul ul li a {
  color: #f68181;
  background: none;
}
#cssmenu.small-screen ul ul li:hover > a,
#cssmenu.small-screen ul ul li.active > a {
  color: #ff0000;
}
#cssmenu.small-screen ul ul,
#cssmenu.small-screen ul ul ul,
#cssmenu.small-screen.align-right ul ul {
  position: relative;
  left: 0;
  width: 100%;
  margin: 0;
  text-align: left;
}
#cssmenu.small-screen > ul > li.has-sub > a:after,
#cssmenu.small-screen > ul > li.has-sub > a:before,
#cssmenu.small-screen ul ul > li.has-sub > a:after,
#cssmenu.small-screen ul ul > li.has-sub > a:before {
  display: none;
}
#cssmenu.small-screen #menu-button {
  display: block;
  padding: 17px;
  color: #f68181;
  cursor: pointer;
  font-size: 12px;
  text-transform: uppercase;
  font-weight: 700;
}
#cssmenu.small-screen #menu-button:after {
  position: absolute;
  top: 22px;
  right: 17px;
  display: block;
  height: 4px;
  width: 20px;
  border-top: 2px solid #f68181;
  border-bottom: 2px solid #f68181;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button:before {
  position: absolute;
  top: 16px;
  right: 17px;
  display: block;
  height: 2px;
  width: 20px;
  background: #f68181;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button.menu-opened:after {
  top: 23px;
  border: 0;
  height: 2px;
  width: 15px;
  background: #ff0000;
  -webkit-transform: rotate(45deg);
  -moz-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  transform: rotate(45deg);
}
#cssmenu.small-screen #menu-button.menu-opened:before {
  top: 23px;
  background: #ff0000;
  width: 15px;
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -ms-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
}
#cssmenu.small-screen .submenu-button {
  position: absolute;
  z-index: 99;
  right: 0;
  top: 0;
  display: block;
  border-left: 1px solid rgba(120, 120, 120, 0.2);
  height: 46px;
  width: 46px;
  cursor: pointer;
}
#cssmenu.small-screen .submenu-button.submenu-opened {
  background: #262626;
}
#cssmenu.small-screen ul ul .submenu-button {
  height: 34px;
  width: 34px;
}
#cssmenu.small-screen .submenu-button:after {
  position: absolute;
  top: 22px;
  right: 19px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:after {
  top: 15px;
  right: 13px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:after {
  background: #ff0000;
}
#cssmenu.small-screen .submenu-button:before {
  position: absolute;
  top: 19px;
  right: 22px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:before {
  top: 12px;
  right: 16px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:before {
  display: none;
}
#cssmenu.small-screen.select-list {
  padding: 5px;
}

$("#cssmenu").menumaker({
    title: "Menu",
    breakpoint: 768,
    format: "multitoggle"
});

但是我认为菜单的布局是不切实际的，所以我改进了你的列表如下

HTML:

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- jQuery -->
<script src="http://code.jquery.com/jquery-latest.min.js"></script>

<!-- MenuMaker Plugin -->
<script src="https://s3.amazonaws.com/menumaker/menumaker.min.js"></script>

<!-- Icon Library -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css">
<meta charset="UTF-8">
<title>Title of the document</title>
</head>

<body>
<div id="cssmenu">
  <ul>
     <li><a href="#" target="_blank"><i class="fa fa-fw fa-asterisk"></i> Components</a>
        <ul>
           <li><a href="#">Widgets</a></li>
           <li><a href="#">Nesteble</a></li>
           <li><a href="#">Range sliders</a></li>
           <li><a href="#">Masonry</a></li>
           <li><a href="#">Animation</a></li>
           <li><a href="#">Sweet Alerts</a></li>
           <li><a href="#">Tree view</a></li>
           <li><a href="#">Tour</a></li>
           <li><a href="#">General Elements</a>
              <ul>
                 <li><a href="#">Menu Level 1</a>
                    <ul>
                       <li><a href="#">Menu Level 1.1</a></li>
                       <li><a href="#">Menu Level 1.2</a></li>
                       <li><a href="#">Menu Level 1.3</a></li>
                    </ul>
                 </li>
              </ul>
           </li>
           <li><a href="#">Form Validation</a></li>
           <li><a href="#">Form Pickers</a></li>
           <li><a href="#">Form Wizard</a></li>
           <li><a href="#">Form Masks</a></li>
           <li><a href="#">Summernote</a></li>
           <li><a href="#">Wysiwig Editors</a></li>
           <li><a href="#">Code Editor</a></li>
           <li><a href="#">Multiple File Upload</a></li>
           <li><a href="#">X-editable</a></li>
           <li><a href="#">Image Crop</a></li>
        </ul>
     </li>
  </ul>
</div>
</body>

</html>

@import url(https://fonts.googleapis.com/css?family=Montserrat:400,700);
#cssmenu,
#cssmenu ul,
#cssmenu ul li,
#cssmenu ul li a,
#cssmenu #menu-button {
  margin: 0;
  padding: 0;
  border: 0;
  list-style: none;
  line-height: 1;
  display: block;
  position: relative;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
}
#cssmenu:after,
#cssmenu > ul:after {
  content: ".";
  display: block;
  clear: both;
  visibility: hidden;
  line-height: 0;
  height: 0;
}
#cssmenu #menu-button {
  display: none;
}
#cssmenu {
  font-family: Montserrat, sans-serif;
  background: #333333;
}
#cssmenu > ul > li {
  float: left;
}
#cssmenu.align-center > ul {
  font-size: 0;
  text-align: center;
}
#cssmenu.align-center > ul > li {
  display: inline-block;
  float: none;
}
#cssmenu.align-center ul ul {
  text-align: left;
}
#cssmenu.align-right > ul > li {
  float: right;
}
#cssmenu > ul > li > a {
  padding: 17px;
  font-size: 12px;
  letter-spacing: 1px;
  text-decoration: none;
  color: #00c7c7;
  font-weight: 700;
  text-transform: uppercase;
}
#cssmenu > ul > li:hover > a {
  color: #00ffff;
}
#cssmenu > ul > li.has-sub > a {
  padding-right: 30px;
}
#cssmenu > ul > li.has-sub > a:after {
  position: absolute;
  top: 22px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu > ul > li.has-sub > a:before {
  position: absolute;
  top: 19px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu > ul > li.has-sub:hover > a:before {
  top: 23px;
  height: 0;
}
#cssmenu ul ul {
  position: absolute;
  left: -9999px;
}
#cssmenu.align-right ul ul {
  text-align: right;
}
#cssmenu ul ul li {
  height: 0;
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu li:hover > ul {
  left: auto;
}
#cssmenu.align-right li:hover > ul {
  left: auto;
  right: 0;
}
#cssmenu li:hover > ul > li {
  height: 35px;
}
#cssmenu ul ul ul {
  margin-left: 100%;
  top: 0;
}
#cssmenu.align-right ul ul ul {
  margin-left: 0;
  margin-right: 100%;
}
#cssmenu ul ul li a {
  border-bottom: 1px solid rgba(150, 150, 150, 0.15);
  padding: 11px 15px;
  width: 170px;
  font-size: 12px;
  text-decoration: none;
  color: #00c7c7;
  font-weight: 400;
  background: #333333;
}
#cssmenu ul ul li:last-child > a,
#cssmenu ul ul li.last-item > a {
  border-bottom: 0;
}
#cssmenu ul ul li:hover > a,
#cssmenu ul ul li a:hover {
  color: #00ffff;
}
#cssmenu ul ul li.has-sub > a:after {
  position: absolute;
  top: 16px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu.align-right ul ul li.has-sub > a:after {
  right: auto;
  left: 11px;
}
#cssmenu ul ul li.has-sub > a:before {
  position: absolute;
  top: 13px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu.align-right ul ul li.has-sub > a:before {
  right: auto;
  left: 14px;
}
#cssmenu ul ul > li.has-sub:hover > a:before {
  top: 17px;
  height: 0;
}
#cssmenu.small-screen {
  width: 100%;
}
#cssmenu.small-screen ul {
  width: 100%;
  display: none;
}
#cssmenu.small-screen.align-center > ul {
  text-align: left;
}
#cssmenu.small-screen ul li {
  width: 100%;
  border-top: 1px solid rgba(120, 120, 120, 0.2);
}
#cssmenu.small-screen ul ul li,
#cssmenu.small-screen li:hover > ul > li {
  height: auto;
}
#cssmenu.small-screen ul li a,
#cssmenu.small-screen ul ul li a {
  width: 100%;
  border-bottom: 0;
}
#cssmenu.small-screen > ul > li {
  float: none;
}
#cssmenu.small-screen ul ul li a {
  padding-left: 25px;
}
#cssmenu.small-screen ul ul ul li a {
  padding-left: 35px;
}
#cssmenu.small-screen ul ul li a {
  color: #00c7c7;
  background: none;
}
#cssmenu.small-screen ul ul li:hover > a,
#cssmenu.small-screen ul ul li.active > a {
  color: #00ffff;
}
#cssmenu.small-screen ul ul,
#cssmenu.small-screen ul ul ul,
#cssmenu.small-screen.align-right ul ul {
  position: relative;
  left: 0;
  width: 100%;
  margin: 0;
  text-align: left;
}
#cssmenu.small-screen > ul > li.has-sub > a:after,
#cssmenu.small-screen > ul > li.has-sub > a:before,
#cssmenu.small-screen ul ul > li.has-sub > a:after,
#cssmenu.small-screen ul ul > li.has-sub > a:before {
  display: none;
}
#cssmenu.small-screen #menu-button {
  display: block;
  padding: 17px;
  color: #00c7c7;
  cursor: pointer;
  font-size: 12px;
  text-transform: uppercase;
  font-weight: 700;
}
#cssmenu.small-screen #menu-button:after {
  position: absolute;
  top: 22px;
  right: 17px;
  display: block;
  height: 4px;
  width: 20px;
  border-top: 2px solid #00c7c7;
  border-bottom: 2px solid #00c7c7;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button:before {
  position: absolute;
  top: 16px;
  right: 17px;
  display: block;
  height: 2px;
  width: 20px;
  background: #00c7c7;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button.menu-opened:after {
  top: 23px;
  border: 0;
  height: 2px;
  width: 15px;
  background: #00ffff;
  -webkit-transform: rotate(45deg);
  -moz-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  transform: rotate(45deg);
}
#cssmenu.small-screen #menu-button.menu-opened:before {
  top: 23px;
  background: #00ffff;
  width: 15px;
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -ms-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
}
#cssmenu.small-screen .submenu-button {
  position: absolute;
  z-index: 99;
  right: 0;
  top: 0;
  display: block;
  border-left: 1px solid rgba(120, 120, 120, 0.2);
  height: 46px;
  width: 46px;
  cursor: pointer;
}
#cssmenu.small-screen .submenu-button.submenu-opened {
  background: #262626;
}
#cssmenu.small-screen ul ul .submenu-button {
  height: 34px;
  width: 34px;
}
#cssmenu.small-screen .submenu-button:after {
  position: absolute;
  top: 22px;
  right: 19px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:after {
  top: 15px;
  right: 13px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:after {
  background: #00ffff;
}
#cssmenu.small-screen .submenu-button:before {
  position: absolute;
  top: 19px;
  right: 22px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:before {
  top: 12px;
  right: 16px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:before {
  display: none;
}
#cssmenu.small-screen.select-list {
  padding: 5px;
}

$("#cssmenu").menumaker({
    title: "Menu",
    breakpoint: 768,
    format: "multitoggle"
});

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- jQuery -->
<script src="http://code.jquery.com/jquery-latest.min.js"></script>

<!-- MenuMaker Plugin -->
<script src="https://s3.amazonaws.com/menumaker/menumaker.min.js"></script>

<!-- Icon Library -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css">
<meta charset="UTF-8">
<title>Title</title>
</head>

<body>
<div id="cssmenu">
  <ul>
     <li><a href="#" target="_blank"><i class="fa fa-fw fa-asterisk"></i> Components</a>
        <ul>
           <li><a href="#">Widgets</a></li>
           <li><a href="#">Nesteble</a></li>
           <li><a href="#">Range sliders</a></li>
           <li><a href="#">Masonry</a></li>
           <li><a href="#">Animation</a></li>
           <li><a href="#">Sweet Alerts</a></li>
           <li><a href="#">Tree view</a></li>
           <li><a href="#">Tour</a></li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-bars"></i> General Elements</a>
        <ul>
           <li><a href="#">Menu Level 1</a>
              <ul>
                 <li><a href="#">Menu Level 1.1</a></li>
                 <li><a href="#">Menu Level 1.2</a></li>
                 <li><a href="#">Menu Level 1.3</a></li>
              </ul>
           </li>
           <li><a href="#">Menu Level 2</a>
              <ul>
                 <li><a href="#">Menu Level 2.1</a>
                    <ul>
                       <li><a href="#">Menu Level 2.1.1</a></li>
                       <li><a href="#">Menu Level 2.1.2</a></li>
                       <li><a href="#">Menu Level 2.1.3</a></li>
                    </ul>
                 </li>
                 <li><a href="#">Menu Level 2.2</a></li>
                 <li><a href="#">Menu Level 2.3</a></li>
                 <li><a href="#">Menu Level 2.4</a></li>
              </ul>
           </li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-circle-o-notch"></i> Forms</a>
        <ul>
           <li><a href="#">Form Validation</a></li>
           <li><a href="#">Form Pickers</a></li>
           <li><a href="#">Form Wizard</a></li>
           <li><a href="#">Form Masks</a></li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-check"></i> Services</a>
        <ul>
           <li><a href="#">Summernote</a></li>
           <li><a href="#">Wysiwig Editors</a></li>
           <li><a href="#">Code Editor</a></li>
           <li><a href="#">Multiple File Upload</a></li>
           <li><a href="#">X-editable</a></li>
           <li><a href="#">Image Crop</a></li>
        </ul>
     </li>
  </ul>
</div>
</body>

</html>

@import url(https://fonts.googleapis.com/css?family=Montserrat:400,700);
#cssmenu,
#cssmenu ul,
#cssmenu ul li,
#cssmenu ul li a,
#cssmenu #menu-button {
  margin: 0;
  padding: 0;
  border: 0;
  list-style: none;
  line-height: 1;
  display: block;
  position: relative;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
}
#cssmenu:after,
#cssmenu > ul:after {
  content: ".";
  display: block;
  clear: both;
  visibility: hidden;
  line-height: 0;
  height: 0;
}
#cssmenu #menu-button {
  display: none;
}
#cssmenu {
  font-family: Montserrat, sans-serif;
  background: #333333;
}
#cssmenu > ul > li {
  float: left;
}
#cssmenu.align-center > ul {
  font-size: 0;
  text-align: center;
}
#cssmenu.align-center > ul > li {
  display: inline-block;
  float: none;
}
#cssmenu.align-center ul ul {
  text-align: left;
}
#cssmenu.align-right > ul > li {
  float: right;
}
#cssmenu > ul > li > a {
  padding: 17px;
  font-size: 12px;
  letter-spacing: 1px;
  text-decoration: none;
  color: #f68181;
  font-weight: 700;
  text-transform: uppercase;
}
#cssmenu > ul > li:hover > a {
  color: #ff0000;
}
#cssmenu > ul > li.has-sub > a {
  padding-right: 30px;
}
#cssmenu > ul > li.has-sub > a:after {
  position: absolute;
  top: 22px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu > ul > li.has-sub > a:before {
  position: absolute;
  top: 19px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu > ul > li.has-sub:hover > a:before {
  top: 23px;
  height: 0;
}
#cssmenu ul ul {
  position: absolute;
  left: -9999px;
}
#cssmenu.align-right ul ul {
  text-align: right;
}
#cssmenu ul ul li {
  height: 0;
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu li:hover > ul {
  left: auto;
}
#cssmenu.align-right li:hover > ul {
  left: auto;
  right: 0;
}
#cssmenu li:hover > ul > li {
  height: 35px;
}
#cssmenu ul ul ul {
  margin-left: 100%;
  top: 0;
}
#cssmenu.align-right ul ul ul {
  margin-left: 0;
  margin-right: 100%;
}
#cssmenu ul ul li a {
  border-bottom: 1px solid rgba(150, 150, 150, 0.15);
  padding: 11px 15px;
  width: 170px;
  font-size: 12px;
  text-decoration: none;
  color: #f68181;
  font-weight: 400;
  background: #333333;
}
#cssmenu ul ul li:last-child > a,
#cssmenu ul ul li.last-item > a {
  border-bottom: 0;
}
#cssmenu ul ul li:hover > a,
#cssmenu ul ul li a:hover {
  color: #ff0000;
}
#cssmenu ul ul li.has-sub > a:after {
  position: absolute;
  top: 16px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu.align-right ul ul li.has-sub > a:after {
  right: auto;
  left: 11px;
}
#cssmenu ul ul li.has-sub > a:before {
  position: absolute;
  top: 13px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu.align-right ul ul li.has-sub > a:before {
  right: auto;
  left: 14px;
}
#cssmenu ul ul > li.has-sub:hover > a:before {
  top: 17px;
  height: 0;
}
#cssmenu.small-screen {
  width: 100%;
}
#cssmenu.small-screen ul {
  width: 100%;
  display: none;
}
#cssmenu.small-screen.align-center > ul {
  text-align: left;
}
#cssmenu.small-screen ul li {
  width: 100%;
  border-top: 1px solid rgba(120, 120, 120, 0.2);
}
#cssmenu.small-screen ul ul li,
#cssmenu.small-screen li:hover > ul > li {
  height: auto;
}
#cssmenu.small-screen ul li a,
#cssmenu.small-screen ul ul li a {
  width: 100%;
  border-bottom: 0;
}
#cssmenu.small-screen > ul > li {
  float: none;
}
#cssmenu.small-screen ul ul li a {
  padding-left: 25px;
}
#cssmenu.small-screen ul ul ul li a {
  padding-left: 35px;
}
#cssmenu.small-screen ul ul li a {
  color: #f68181;
  background: none;
}
#cssmenu.small-screen ul ul li:hover > a,
#cssmenu.small-screen ul ul li.active > a {
  color: #ff0000;
}
#cssmenu.small-screen ul ul,
#cssmenu.small-screen ul ul ul,
#cssmenu.small-screen.align-right ul ul {
  position: relative;
  left: 0;
  width: 100%;
  margin: 0;
  text-align: left;
}
#cssmenu.small-screen > ul > li.has-sub > a:after,
#cssmenu.small-screen > ul > li.has-sub > a:before,
#cssmenu.small-screen ul ul > li.has-sub > a:after,
#cssmenu.small-screen ul ul > li.has-sub > a:before {
  display: none;
}
#cssmenu.small-screen #menu-button {
  display: block;
  padding: 17px;
  color: #f68181;
  cursor: pointer;
  font-size: 12px;
  text-transform: uppercase;
  font-weight: 700;
}
#cssmenu.small-screen #menu-button:after {
  position: absolute;
  top: 22px;
  right: 17px;
  display: block;
  height: 4px;
  width: 20px;
  border-top: 2px solid #f68181;
  border-bottom: 2px solid #f68181;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button:before {
  position: absolute;
  top: 16px;
  right: 17px;
  display: block;
  height: 2px;
  width: 20px;
  background: #f68181;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button.menu-opened:after {
  top: 23px;
  border: 0;
  height: 2px;
  width: 15px;
  background: #ff0000;
  -webkit-transform: rotate(45deg);
  -moz-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  transform: rotate(45deg);
}
#cssmenu.small-screen #menu-button.menu-opened:before {
  top: 23px;
  background: #ff0000;
  width: 15px;
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -ms-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
}
#cssmenu.small-screen .submenu-button {
  position: absolute;
  z-index: 99;
  right: 0;
  top: 0;
  display: block;
  border-left: 1px solid rgba(120, 120, 120, 0.2);
  height: 46px;
  width: 46px;
  cursor: pointer;
}
#cssmenu.small-screen .submenu-button.submenu-opened {
  background: #262626;
}
#cssmenu.small-screen ul ul .submenu-button {
  height: 34px;
  width: 34px;
}
#cssmenu.small-screen .submenu-button:after {
  position: absolute;
  top: 22px;
  right: 19px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:after {
  top: 15px;
  right: 13px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:after {
  background: #ff0000;
}
#cssmenu.small-screen .submenu-button:before {
  position: absolute;
  top: 19px;
  right: 22px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:before {
  top: 12px;
  right: 16px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:before {
  display: none;
}
#cssmenu.small-screen.select-list {
  padding: 5px;
}

$("#cssmenu").menumaker({
    title: "Menu",
    breakpoint: 768,
    format: "multitoggle"
});

Javascript:

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- jQuery -->
<script src="http://code.jquery.com/jquery-latest.min.js"></script>

<!-- MenuMaker Plugin -->
<script src="https://s3.amazonaws.com/menumaker/menumaker.min.js"></script>

<!-- Icon Library -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css">
<meta charset="UTF-8">
<title>Title of the document</title>
</head>

<body>
<div id="cssmenu">
  <ul>
     <li><a href="#" target="_blank"><i class="fa fa-fw fa-asterisk"></i> Components</a>
        <ul>
           <li><a href="#">Widgets</a></li>
           <li><a href="#">Nesteble</a></li>
           <li><a href="#">Range sliders</a></li>
           <li><a href="#">Masonry</a></li>
           <li><a href="#">Animation</a></li>
           <li><a href="#">Sweet Alerts</a></li>
           <li><a href="#">Tree view</a></li>
           <li><a href="#">Tour</a></li>
           <li><a href="#">General Elements</a>
              <ul>
                 <li><a href="#">Menu Level 1</a>
                    <ul>
                       <li><a href="#">Menu Level 1.1</a></li>
                       <li><a href="#">Menu Level 1.2</a></li>
                       <li><a href="#">Menu Level 1.3</a></li>
                    </ul>
                 </li>
              </ul>
           </li>
           <li><a href="#">Form Validation</a></li>
           <li><a href="#">Form Pickers</a></li>
           <li><a href="#">Form Wizard</a></li>
           <li><a href="#">Form Masks</a></li>
           <li><a href="#">Summernote</a></li>
           <li><a href="#">Wysiwig Editors</a></li>
           <li><a href="#">Code Editor</a></li>
           <li><a href="#">Multiple File Upload</a></li>
           <li><a href="#">X-editable</a></li>
           <li><a href="#">Image Crop</a></li>
        </ul>
     </li>
  </ul>
</div>
</body>

</html>

@import url(https://fonts.googleapis.com/css?family=Montserrat:400,700);
#cssmenu,
#cssmenu ul,
#cssmenu ul li,
#cssmenu ul li a,
#cssmenu #menu-button {
  margin: 0;
  padding: 0;
  border: 0;
  list-style: none;
  line-height: 1;
  display: block;
  position: relative;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
}
#cssmenu:after,
#cssmenu > ul:after {
  content: ".";
  display: block;
  clear: both;
  visibility: hidden;
  line-height: 0;
  height: 0;
}
#cssmenu #menu-button {
  display: none;
}
#cssmenu {
  font-family: Montserrat, sans-serif;
  background: #333333;
}
#cssmenu > ul > li {
  float: left;
}
#cssmenu.align-center > ul {
  font-size: 0;
  text-align: center;
}
#cssmenu.align-center > ul > li {
  display: inline-block;
  float: none;
}
#cssmenu.align-center ul ul {
  text-align: left;
}
#cssmenu.align-right > ul > li {
  float: right;
}
#cssmenu > ul > li > a {
  padding: 17px;
  font-size: 12px;
  letter-spacing: 1px;
  text-decoration: none;
  color: #00c7c7;
  font-weight: 700;
  text-transform: uppercase;
}
#cssmenu > ul > li:hover > a {
  color: #00ffff;
}
#cssmenu > ul > li.has-sub > a {
  padding-right: 30px;
}
#cssmenu > ul > li.has-sub > a:after {
  position: absolute;
  top: 22px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu > ul > li.has-sub > a:before {
  position: absolute;
  top: 19px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu > ul > li.has-sub:hover > a:before {
  top: 23px;
  height: 0;
}
#cssmenu ul ul {
  position: absolute;
  left: -9999px;
}
#cssmenu.align-right ul ul {
  text-align: right;
}
#cssmenu ul ul li {
  height: 0;
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu li:hover > ul {
  left: auto;
}
#cssmenu.align-right li:hover > ul {
  left: auto;
  right: 0;
}
#cssmenu li:hover > ul > li {
  height: 35px;
}
#cssmenu ul ul ul {
  margin-left: 100%;
  top: 0;
}
#cssmenu.align-right ul ul ul {
  margin-left: 0;
  margin-right: 100%;
}
#cssmenu ul ul li a {
  border-bottom: 1px solid rgba(150, 150, 150, 0.15);
  padding: 11px 15px;
  width: 170px;
  font-size: 12px;
  text-decoration: none;
  color: #00c7c7;
  font-weight: 400;
  background: #333333;
}
#cssmenu ul ul li:last-child > a,
#cssmenu ul ul li.last-item > a {
  border-bottom: 0;
}
#cssmenu ul ul li:hover > a,
#cssmenu ul ul li a:hover {
  color: #00ffff;
}
#cssmenu ul ul li.has-sub > a:after {
  position: absolute;
  top: 16px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu.align-right ul ul li.has-sub > a:after {
  right: auto;
  left: 11px;
}
#cssmenu ul ul li.has-sub > a:before {
  position: absolute;
  top: 13px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu.align-right ul ul li.has-sub > a:before {
  right: auto;
  left: 14px;
}
#cssmenu ul ul > li.has-sub:hover > a:before {
  top: 17px;
  height: 0;
}
#cssmenu.small-screen {
  width: 100%;
}
#cssmenu.small-screen ul {
  width: 100%;
  display: none;
}
#cssmenu.small-screen.align-center > ul {
  text-align: left;
}
#cssmenu.small-screen ul li {
  width: 100%;
  border-top: 1px solid rgba(120, 120, 120, 0.2);
}
#cssmenu.small-screen ul ul li,
#cssmenu.small-screen li:hover > ul > li {
  height: auto;
}
#cssmenu.small-screen ul li a,
#cssmenu.small-screen ul ul li a {
  width: 100%;
  border-bottom: 0;
}
#cssmenu.small-screen > ul > li {
  float: none;
}
#cssmenu.small-screen ul ul li a {
  padding-left: 25px;
}
#cssmenu.small-screen ul ul ul li a {
  padding-left: 35px;
}
#cssmenu.small-screen ul ul li a {
  color: #00c7c7;
  background: none;
}
#cssmenu.small-screen ul ul li:hover > a,
#cssmenu.small-screen ul ul li.active > a {
  color: #00ffff;
}
#cssmenu.small-screen ul ul,
#cssmenu.small-screen ul ul ul,
#cssmenu.small-screen.align-right ul ul {
  position: relative;
  left: 0;
  width: 100%;
  margin: 0;
  text-align: left;
}
#cssmenu.small-screen > ul > li.has-sub > a:after,
#cssmenu.small-screen > ul > li.has-sub > a:before,
#cssmenu.small-screen ul ul > li.has-sub > a:after,
#cssmenu.small-screen ul ul > li.has-sub > a:before {
  display: none;
}
#cssmenu.small-screen #menu-button {
  display: block;
  padding: 17px;
  color: #00c7c7;
  cursor: pointer;
  font-size: 12px;
  text-transform: uppercase;
  font-weight: 700;
}
#cssmenu.small-screen #menu-button:after {
  position: absolute;
  top: 22px;
  right: 17px;
  display: block;
  height: 4px;
  width: 20px;
  border-top: 2px solid #00c7c7;
  border-bottom: 2px solid #00c7c7;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button:before {
  position: absolute;
  top: 16px;
  right: 17px;
  display: block;
  height: 2px;
  width: 20px;
  background: #00c7c7;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button.menu-opened:after {
  top: 23px;
  border: 0;
  height: 2px;
  width: 15px;
  background: #00ffff;
  -webkit-transform: rotate(45deg);
  -moz-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  transform: rotate(45deg);
}
#cssmenu.small-screen #menu-button.menu-opened:before {
  top: 23px;
  background: #00ffff;
  width: 15px;
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -ms-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
}
#cssmenu.small-screen .submenu-button {
  position: absolute;
  z-index: 99;
  right: 0;
  top: 0;
  display: block;
  border-left: 1px solid rgba(120, 120, 120, 0.2);
  height: 46px;
  width: 46px;
  cursor: pointer;
}
#cssmenu.small-screen .submenu-button.submenu-opened {
  background: #262626;
}
#cssmenu.small-screen ul ul .submenu-button {
  height: 34px;
  width: 34px;
}
#cssmenu.small-screen .submenu-button:after {
  position: absolute;
  top: 22px;
  right: 19px;
  width: 8px;
  height: 2px;
  display: block;
  background: #00c7c7;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:after {
  top: 15px;
  right: 13px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:after {
  background: #00ffff;
}
#cssmenu.small-screen .submenu-button:before {
  position: absolute;
  top: 19px;
  right: 22px;
  display: block;
  width: 2px;
  height: 8px;
  background: #00c7c7;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:before {
  top: 12px;
  right: 16px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:before {
  display: none;
}
#cssmenu.small-screen.select-list {
  padding: 5px;
}

$("#cssmenu").menumaker({
    title: "Menu",
    breakpoint: 768,
    format: "multitoggle"
});

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- jQuery -->
<script src="http://code.jquery.com/jquery-latest.min.js"></script>

<!-- MenuMaker Plugin -->
<script src="https://s3.amazonaws.com/menumaker/menumaker.min.js"></script>

<!-- Icon Library -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css">
<meta charset="UTF-8">
<title>Title</title>
</head>

<body>
<div id="cssmenu">
  <ul>
     <li><a href="#" target="_blank"><i class="fa fa-fw fa-asterisk"></i> Components</a>
        <ul>
           <li><a href="#">Widgets</a></li>
           <li><a href="#">Nesteble</a></li>
           <li><a href="#">Range sliders</a></li>
           <li><a href="#">Masonry</a></li>
           <li><a href="#">Animation</a></li>
           <li><a href="#">Sweet Alerts</a></li>
           <li><a href="#">Tree view</a></li>
           <li><a href="#">Tour</a></li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-bars"></i> General Elements</a>
        <ul>
           <li><a href="#">Menu Level 1</a>
              <ul>
                 <li><a href="#">Menu Level 1.1</a></li>
                 <li><a href="#">Menu Level 1.2</a></li>
                 <li><a href="#">Menu Level 1.3</a></li>
              </ul>
           </li>
           <li><a href="#">Menu Level 2</a>
              <ul>
                 <li><a href="#">Menu Level 2.1</a>
                    <ul>
                       <li><a href="#">Menu Level 2.1.1</a></li>
                       <li><a href="#">Menu Level 2.1.2</a></li>
                       <li><a href="#">Menu Level 2.1.3</a></li>
                    </ul>
                 </li>
                 <li><a href="#">Menu Level 2.2</a></li>
                 <li><a href="#">Menu Level 2.3</a></li>
                 <li><a href="#">Menu Level 2.4</a></li>
              </ul>
           </li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-circle-o-notch"></i> Forms</a>
        <ul>
           <li><a href="#">Form Validation</a></li>
           <li><a href="#">Form Pickers</a></li>
           <li><a href="#">Form Wizard</a></li>
           <li><a href="#">Form Masks</a></li>
        </ul>
     </li>
     <li><a href="#"><i class="fa fa-fw fa-check"></i> Services</a>
        <ul>
           <li><a href="#">Summernote</a></li>
           <li><a href="#">Wysiwig Editors</a></li>
           <li><a href="#">Code Editor</a></li>
           <li><a href="#">Multiple File Upload</a></li>
           <li><a href="#">X-editable</a></li>
           <li><a href="#">Image Crop</a></li>
        </ul>
     </li>
  </ul>
</div>
</body>

</html>

@import url(https://fonts.googleapis.com/css?family=Montserrat:400,700);
#cssmenu,
#cssmenu ul,
#cssmenu ul li,
#cssmenu ul li a,
#cssmenu #menu-button {
  margin: 0;
  padding: 0;
  border: 0;
  list-style: none;
  line-height: 1;
  display: block;
  position: relative;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
}
#cssmenu:after,
#cssmenu > ul:after {
  content: ".";
  display: block;
  clear: both;
  visibility: hidden;
  line-height: 0;
  height: 0;
}
#cssmenu #menu-button {
  display: none;
}
#cssmenu {
  font-family: Montserrat, sans-serif;
  background: #333333;
}
#cssmenu > ul > li {
  float: left;
}
#cssmenu.align-center > ul {
  font-size: 0;
  text-align: center;
}
#cssmenu.align-center > ul > li {
  display: inline-block;
  float: none;
}
#cssmenu.align-center ul ul {
  text-align: left;
}
#cssmenu.align-right > ul > li {
  float: right;
}
#cssmenu > ul > li > a {
  padding: 17px;
  font-size: 12px;
  letter-spacing: 1px;
  text-decoration: none;
  color: #f68181;
  font-weight: 700;
  text-transform: uppercase;
}
#cssmenu > ul > li:hover > a {
  color: #ff0000;
}
#cssmenu > ul > li.has-sub > a {
  padding-right: 30px;
}
#cssmenu > ul > li.has-sub > a:after {
  position: absolute;
  top: 22px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu > ul > li.has-sub > a:before {
  position: absolute;
  top: 19px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu > ul > li.has-sub:hover > a:before {
  top: 23px;
  height: 0;
}
#cssmenu ul ul {
  position: absolute;
  left: -9999px;
}
#cssmenu.align-right ul ul {
  text-align: right;
}
#cssmenu ul ul li {
  height: 0;
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu li:hover > ul {
  left: auto;
}
#cssmenu.align-right li:hover > ul {
  left: auto;
  right: 0;
}
#cssmenu li:hover > ul > li {
  height: 35px;
}
#cssmenu ul ul ul {
  margin-left: 100%;
  top: 0;
}
#cssmenu.align-right ul ul ul {
  margin-left: 0;
  margin-right: 100%;
}
#cssmenu ul ul li a {
  border-bottom: 1px solid rgba(150, 150, 150, 0.15);
  padding: 11px 15px;
  width: 170px;
  font-size: 12px;
  text-decoration: none;
  color: #f68181;
  font-weight: 400;
  background: #333333;
}
#cssmenu ul ul li:last-child > a,
#cssmenu ul ul li.last-item > a {
  border-bottom: 0;
}
#cssmenu ul ul li:hover > a,
#cssmenu ul ul li a:hover {
  color: #ff0000;
}
#cssmenu ul ul li.has-sub > a:after {
  position: absolute;
  top: 16px;
  right: 11px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu.align-right ul ul li.has-sub > a:after {
  right: auto;
  left: 11px;
}
#cssmenu ul ul li.has-sub > a:before {
  position: absolute;
  top: 13px;
  right: 14px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
  -webkit-transition: all .25s ease;
  -moz-transition: all .25s ease;
  -ms-transition: all .25s ease;
  -o-transition: all .25s ease;
  transition: all .25s ease;
}
#cssmenu.align-right ul ul li.has-sub > a:before {
  right: auto;
  left: 14px;
}
#cssmenu ul ul > li.has-sub:hover > a:before {
  top: 17px;
  height: 0;
}
#cssmenu.small-screen {
  width: 100%;
}
#cssmenu.small-screen ul {
  width: 100%;
  display: none;
}
#cssmenu.small-screen.align-center > ul {
  text-align: left;
}
#cssmenu.small-screen ul li {
  width: 100%;
  border-top: 1px solid rgba(120, 120, 120, 0.2);
}
#cssmenu.small-screen ul ul li,
#cssmenu.small-screen li:hover > ul > li {
  height: auto;
}
#cssmenu.small-screen ul li a,
#cssmenu.small-screen ul ul li a {
  width: 100%;
  border-bottom: 0;
}
#cssmenu.small-screen > ul > li {
  float: none;
}
#cssmenu.small-screen ul ul li a {
  padding-left: 25px;
}
#cssmenu.small-screen ul ul ul li a {
  padding-left: 35px;
}
#cssmenu.small-screen ul ul li a {
  color: #f68181;
  background: none;
}
#cssmenu.small-screen ul ul li:hover > a,
#cssmenu.small-screen ul ul li.active > a {
  color: #ff0000;
}
#cssmenu.small-screen ul ul,
#cssmenu.small-screen ul ul ul,
#cssmenu.small-screen.align-right ul ul {
  position: relative;
  left: 0;
  width: 100%;
  margin: 0;
  text-align: left;
}
#cssmenu.small-screen > ul > li.has-sub > a:after,
#cssmenu.small-screen > ul > li.has-sub > a:before,
#cssmenu.small-screen ul ul > li.has-sub > a:after,
#cssmenu.small-screen ul ul > li.has-sub > a:before {
  display: none;
}
#cssmenu.small-screen #menu-button {
  display: block;
  padding: 17px;
  color: #f68181;
  cursor: pointer;
  font-size: 12px;
  text-transform: uppercase;
  font-weight: 700;
}
#cssmenu.small-screen #menu-button:after {
  position: absolute;
  top: 22px;
  right: 17px;
  display: block;
  height: 4px;
  width: 20px;
  border-top: 2px solid #f68181;
  border-bottom: 2px solid #f68181;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button:before {
  position: absolute;
  top: 16px;
  right: 17px;
  display: block;
  height: 2px;
  width: 20px;
  background: #f68181;
  content: '';
  box-sizing: content-box;
}
#cssmenu.small-screen #menu-button.menu-opened:after {
  top: 23px;
  border: 0;
  height: 2px;
  width: 15px;
  background: #ff0000;
  -webkit-transform: rotate(45deg);
  -moz-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  -o-transform: rotate(45deg);
  transform: rotate(45deg);
}
#cssmenu.small-screen #menu-button.menu-opened:before {
  top: 23px;
  background: #ff0000;
  width: 15px;
  -webkit-transform: rotate(-45deg);
  -moz-transform: rotate(-45deg);
  -ms-transform: rotate(-45deg);
  -o-transform: rotate(-45deg);
  transform: rotate(-45deg);
}
#cssmenu.small-screen .submenu-button {
  position: absolute;
  z-index: 99;
  right: 0;
  top: 0;
  display: block;
  border-left: 1px solid rgba(120, 120, 120, 0.2);
  height: 46px;
  width: 46px;
  cursor: pointer;
}
#cssmenu.small-screen .submenu-button.submenu-opened {
  background: #262626;
}
#cssmenu.small-screen ul ul .submenu-button {
  height: 34px;
  width: 34px;
}
#cssmenu.small-screen .submenu-button:after {
  position: absolute;
  top: 22px;
  right: 19px;
  width: 8px;
  height: 2px;
  display: block;
  background: #f68181;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:after {
  top: 15px;
  right: 13px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:after {
  background: #ff0000;
}
#cssmenu.small-screen .submenu-button:before {
  position: absolute;
  top: 19px;
  right: 22px;
  display: block;
  width: 2px;
  height: 8px;
  background: #f68181;
  content: '';
}
#cssmenu.small-screen ul ul .submenu-button:before {
  top: 12px;
  right: 16px;
}
#cssmenu.small-screen .submenu-button.submenu-opened:before {
  display: none;
}
#cssmenu.small-screen.select-list {
  padding: 5px;
}

$("#cssmenu").menumaker({
    title: "Menu",
    breakpoint: 768,
    format: "multitoggle"
});

---

我希望我的解决方案能帮助你

你的css与标记不匹配？css代码是另一个样式表的一部分，我不能在这里包含整个文件，但这段代码是通过不考虑#wrapper.放大的ID来匹配的。那么调整一下，我们应该怎么知道这一点。