JSFiddle - React, Tailwind, and code Playground

HTML

<div id="navigation" class="navigation">
    <div id="dropmenu" class="dropmenu">
        <login>
            <ul>
                <li> <a href="#" ><span id="cart-button" class="flaticon flaticon-cart" aria-hidden="true"></span></a>

                </li>
                <li> <a href="javascript:void(0);">Dropdown C</a>

                    <ul>
                        <li><a href="#" >Option 1</a>
                        </li>
                        <li><a href="#" >Option 2</a>
                        </li>
                        <li><a href="#" >Option 3</a>
                        </li>
                    </ul>
                </li>
            </ul>
        </login>
        <ul>
            <li> <a href="/">Home</a>

            </li>
            <li> <a href="javascript:void(0);" >Dropdown A</a>

                <div class="sub-menu">
                    <div class="sub-menu-inner">
                        <div>
                            <ul>
                                <li><a href="#" >Dropdown A - 1</a>
                                </li>
                                <li><a href="#" >Dropdown A - 2</a>
                                </li>
                            </ul>
                        </div>
                    </div>
                    <!-- /sub-menu-inner -->
                </div>
                <!-- /sub-menu -->
            </li>
            
            <li> <a href="javascript:void(0);" >Dropdown B</a>

                <div class="sub-menu">
                    <div class="sub-menu-inner">
                        <div>
                            <ul>
                                <li> <a href="#" >Dropdown B - 1</a>

                                    <ul>
                                        <li><a href="#" >Dropdown B - 1 - 1</a>
                                        </li>
                                    </ul>
                                </li>
                                <li><a href="#" >Dropdown...

CSS

.navigation {
    width: 100%;
    height: 36px;
    background-color: rgb(243, 245, 245);
}
.dropmenu {
    position: relative;
    width: 100%;
    height: 36px;
    font-weight: bold;
    background: #3e494b;
    /* menu background color */
}
.dropmenu ul {
    list-style-type: none;
    z-index: 50;
}
/* first level ul style */

/* .dropmenu > ul, */
 .dropmenu .sub-menu-inner {
    margin: 0 auto;
    /*
    background: rgb(130, 160, 46);
    background: rgba(255, 160, 46, 0.92);
    */
}
.dropmenu > ul > li {
    float: left;
    z-index: 50;
}
.dropmenu > ul > li:nth-of-type(1) {
    width: 187px;
}
.dropmenu > ul > li > a {
    display: inline-block;
    padding: 10px 20px;
    color: #b1b6b9;
    /* grey menu text color */
}
.dropmenu > ul > li > a:hover {
    padding: 10px 20px 10px;
    /* correlation with underline */
    /*
    border-top: 3px solid;
    border-top-color: #b1b6b9;
    */
    background-color: #596466;
    /* #3e494b; /* dark grey */
    color: #ffffff;
}
.dropmenu > ul > li.toggled > a, .dropmenu > ul > li.toggled > a:hover {
    padding: 10px 20px 10px;
    /* correlation with underline */
    /*
    border-top: 3px solid;
    border-top-color: #b1b6b9;
    */
    background-color: #596466;
    /* #3e494b; /* dark grey */
    color: #ffffff;
}
/* sub-menu */
 .dropmenu .sub-menu {
    display: none;
    position: absolute;
    /* background: #00a3da; */
    width: 100%;
    left: 0;
    -webkit-box-shadow: 0 4px 5px -5px #000000;
    -moz-box-shadow: 0 4px 5px -5px #000000;
    box-shadow: 0 4px 5px -5px #000000;
}
.toggled .sub-menu {
    display: block;
    width: 100%;
    background: #596466;
    /* sub menu color */
    /* border: 1px solid red; /**/
}
.dropmenu .sub-menu-inner > div {
    width: 100%;
    height: 100%;
    float: left;
    /* border: 1px solid green; /**/
}
/*
.dropmenu .sub-menu-inner > div > ul {
    
}
/**/
 .dropmenu .sub-menu-inner > div > ul > li {
    display: inline;
    overflow: hidden;
    position:...

JavaScript

var currentTop = -1;
var currentSub = -1;
var currentProfile = -1;
//var topMenu = '';
//var subMenu = '';
var lastToggled = '';

function InitNav() {
    //$body.on('click', '#dropmenu > ul > li > a', ToggleTop);
    $('#dropmenu > ul > li > a', 'body').mouseenter(ToggleTop);
    $('#dropmenu', 'body').mouseleave(ToggleTop);

    $body.on('click', '#dropmenu > ul > li ul > li > a', ToggleSub);
    $('#dropmenu login a', 'body').mouseenter(ToggleProfileIn).mouseleave(ToggleProfileOut);
    $body.on('click', '#dropmenu login a', ToggleProfile);
}

function ToggleTop(e) {
    var $listItems = $('#dropmenu > ul > li');

    if (currentProfile !== -1) { // reset profile if needed
        lastToggled.removeClass('toggled');
    }

    if (currentTop !== -1) { // reset top menu
        $listItems.eq(currentTop).removeClass('toggled');
    }

    var $currentTarg = $(e.currentTarget);
    var $item = $currentTarg.parent('li');
    var index = $item.index();

    if (currentTop === index) { // reset
        $item.removeClass('toggled');
        currentTop = -1;
    } else { // set
        $item.addClass('toggled');
        currentTop = index;
    }


    return false;
}

function ToggleSub(e) {
    var $listItems = $('#dropmenu .sub-menu-inner > div > ul > li');

    if (currentSub !== -1) { // reset
        $listItems.removeClass('selected');
    }

    var $currentTarg = $(e.currentTarget);
    var $item = $currentTarg.closest('#dropmenu .sub-menu-inner > div > ul > li');
    var index = $item.index();

    // set
    $item.addClass('selected');
    currentSub = index;

    return false;
}

function ToggleProfileIn(e) {
    var $listItems = $('#dropmenu > ul > li');

    if (currentTop !== -1) { // reset
        lastToggled = $listItems.eq(currentTop).removeClass('toggled');
    }
}

function ToggleProfile(e) {
    currentTop = -1;

    var $listItems = $('#dropmenu login > ul > li');

    if (currentProfile !== -1) { // reset
       ...