JSFiddle - React, Tailwind, and code Playground

HTML

<div id="mainMenu">
    <ul>
        <li><a href="#">1st click</a>
        </li>
        <li><a href="#">2nd click</a>
        </li>
    </ul>
</div>
<div id='subMenu'>
    <ul>
        <li class='has-sub'> <a href='#'><span>1-1</span></a>
        <ul>
                <li><a href="#"><span>1-1-1</span></a>
                </li>
                <li class='last'><a href="#"><span>1-1-2</span></a>
                </li>
            </ul>
        </li>
        <li class='has-sub'><a href='#'><span>1-2</span></a>

            <ul>
                <li><a href="#"><span>1-2-1</span></a>
                </li>
                <li class='last'><a href="#"><span>1-2-1</span></a>
                </li>
            </ul>
        </li>
        <li><a href='#'><span>1-3</span></a>
        </li>
        <li class='last'><a href='#'><span>1-4</span></a>
        </li>
    </ul>
    <ul>
        <li><a href='#'><span>2-1</span></a>
        </li>
        <li class='last'><a href='#'><span>2-1</span></a>
        </li>
    </ul>
</div>
<div >
<p>
cuerpo </p>

</div>

CSS

ul {
    list-style: none;
}
#mainMenu li {
    display: inline;
    padding: 10px;
    background-color: lightgrey;
}
#mainMenu > ul > li.active {
    border-bottom: none;
}
#mainMenu > ul > li.active > a {
    color: #fff;
    background-color: #616161;
}
#subMenu, #subMenu ul, #subMenu li, #subMenu a {
    margin: 0;
    padding: 0;
    border: 0;
    list-style: none;
    font-weight: normal;
    text-decoration: none;
    line-height: 1;
    position: relative;
}
#subMenu ul {
    display: none;
}
#subMenu a {
    line-height: 1.3;
}
#subMenu {
    width: 200px;
    background: #fff;
}
#subMenu > ul > li {
    margin: 0 0 1px 0;
}
#subMenu > ul > li:last-child {
    margin: 0;
}
#subMenu > ul > li > a {
    font-size: 14px;
    display: block;
    color: #ffffff;
    background: #616161;
}
#subMenu > ul > li > a > span {
    display: block;
    padding: 6px 10px;
}
#subMenu > ul > li > a:hover {
    text-decoration: none;
}
#subMenu > ul > li.active {
    border-bottom: none;
}
#subMenu > ul > li.active > a {
    color: #fff;
}
#subMenu > ul > li.active > a span {
    background-color: #fa9322;
}
#subMenu > ul > li.has-sub > a span {
    position: relative;
}
#subMenu > ul > li.has-sub > a span:after {
    position: absolute;
    top: 5px;
    right: 5px;
    font-family:'FontAwesome';
    content:"\f116";
}
#subMenu > ul > li.has-sub.active > a span {
    position: relative;
}
#subMenu > ul > li.has-sub.active > a span:after {
    position: absolute;
    top: 5px;
    right: 5px;
    font-family:'FontAwesome';
    content:"\f117";
}
#subMenu .icon-user {
    margin-right: 7px;
    color: #eaeaea;
}

JavaScript

$(function () {
    var checkElement;
    $('#mainMenu > ul > li > a').click(function () {
        $('#subMenu li.active').removeClass('active');
        if(undefined != checkElement ){
            checkElement.slideUp('normal');
        }
        var position = $(this).parent().index() + 1;
        $('#mainMenu li a').not($(this)).parents('li').removeClass('active');
        $(this).closest('li').toggleClass('active');
        if ($(this).parents('li').hasClass('active')) {
            $('#subMenu > ul').hide();
            $('#subMenu > ul:nth-child('+position+')').show();
        } else {
            $('#subMenu > ul').hide();
        }
    });


    $('#subMenu > ul > li > a').click(function () {
        $('#subMenu li').removeClass('active');
        $(this).closest('li').addClass('active');
        if(undefined != checkElement ){
            checkElement.slideUp('normal');
        }
        checkElement = $(this).next();
        if ((checkElement.is('ul')) && (checkElement.is(':visible'))) {
            $(this).closest('li').removeClass('active');
            checkElement.slideUp('normal');
        }
        if ((checkElement.is('ul')) && (!checkElement.is(':visible'))) {
            $('#subMenu ul ul:visible').slideUp('normal');
            checkElement.slideDown('normal');
        }
        if ($(this).closest('li').find('ul').children().length == 0) {
            return true;
        } else {
            return false;
        }
    });
});