<!-- Latest compiled and minified CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css">
<!-- <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> -->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
<!-- Latest compiled JavaScript -->
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/js/bootstrap.min.js"></script>

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
    <!-- Navigation -->
    <nav class="navbar navbar-default navbar-fixed-top" role="navigation">
        <div class="container">
            <!-- Brand and toggle get grouped for better mobile display -->
            <div class="navbar-header">
                <button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1">
                    <span class="sr-only">Toggle navigation</span>
                    <span class="icon-bar"></span>
                    <span class="icon-bar"></span>
                    <span class="icon-bar"></span>
                </button>
                <a class="navbar-brand" href="#">Bootstrap Nav</a>
            </div>
            <!-- Collect the nav links, forms, and other content for toggling -->
            <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
                <ul class="nav navbar-nav">
                    <li class="active"><a href="#">Home</a></li>
                    <!-- Level 1 -->
                    <li class="dropdown">
                        <a href="#" class="dropdown-toggle" data-toggle="dropdown">Menu <b class="caret"></b></a>
                        <ul class="dropdown-menu multi-level">
                            <li><a href="#">Level 1</a></li>                                                       
                            <li class="dropdown-submenu">
                                <a href="#" class="dropdown-toggle" data-toggle="dropdown">Level 1</a>
                                <!-- Level 2 -->
                                <ul class="dropdown-menu">
                                    <li><a href="#">Level 2</a></li>                                    
                                    <li class="dropdown-submenu">
                                        <a href="#" class="dropdown-toggle" data-toggle="dropdown">Level 2</a>
                                        <!-- Level 3 -->
                                        <ul class="dropdown-menu">
                                            <li><a href="#">Level 3</a></li>
                                            <li class="dropdown-submenu">
                                                <a href="#" class="dropdown-toggle" data-toggle="dropdown">Level 3</a>
                                                <!-- Level 4 -->
                                                <ul class="dropdown-menu">
                                                    <li><a href="#">Level 4</a></li>
                                                    <li><a href="#">Level 4</a></li>
                                                    <li><a href="#">Level 4</a></li>          
                                                </ul>
                                            </li>
                                        </ul>
                                    </li>
                                </ul>
                            </li>
                        </ul>
                    </li>                    
                </ul>        
            </div>
            <!-- /.navbar-collapse -->
        </div>
        <!-- /.container -->
    </nav>

</body>

body {
    padding-top: 70px;
        /* Required padding for .navbar-fixed-top. Remove if using .navbar-static-top. Change if height of navigation changes. */
}

.dropdown-submenu {
    position: relative;
}

.dropdown-submenu>.dropdown-menu {
    top: 0;
    left: 100%;
    margin-top: -6px;
    margin-left: -1px;
    -webkit-border-radius: 0 6px 6px 6px;
    -moz-border-radius: 0 6px 6px;
    border-radius: 0 6px 6px 6px;
}

.dropdown:hover>.dropdown-menu {
    display: block;
}

.dropdown-submenu:hover>.dropdown-menu {
    display: block;
}

.dropdown-submenu>a:after {
    display: block;
    content: " ";
    float: right;
    width: 0;
    height: 0;
    border-color: transparent;
    border-style: solid;
    border-width: 5px 0 5px 5px;
    border-left-color: #ccc;
    margin-top: 5px;
    margin-right: -10px;
}

.dropdown-submenu:hover>a:after {
    border-left-color: #fff;
}