JSFiddle - React, Tailwind, and code Playground
HTML
<ul class="dropdown">
<li><a href="#" class="noclick nojs">Select your Topic</a>
<ul class="nojs" >
<li><a href="#">Link 1</a></li>
<li><a href="#">Link 2</a></li>
<li><a href="#">Link 3</a></li>
</ul>
</li>
<li><a href="#" class="noclick nojs">Select your Industry</a>
<ul class="nojs" >
<li><a href="#">Link 1</a></li>
<li><a href="#">Link 2</a></li>
<li><a href="#">Link 3</a></li>
</ul>
</li>
<li><a href="#" class="noclick nojs">Select your Category</a>
<ul class="nojs" >
<li><a href="#">Link 1</a></li>
<li><a href="#">Link 2</a></li>
<li><a href="#">Link 3</a></li>
</ul>
</li>
</ul>
CSS
body { padding:10px; font:12px Arial; }
a { text-decoration:none; }
.dropdown { padding:5px; overflow:hidden; }
.dropdown > li { float:left; background:#efefef; border-right:#666 1px dotted; }
.dropdown > li:hover { background:#eee; }
.dropdown > li a { display:inline-block; padding:10px; }
.dropdown > li.selected > a,
.dropdown > li a:hover { background:#999; color:#fff; }
.dropdown > li > ul { display:none; }
.dropdown > li > ul a { padding:5px; }
JavaScript
$('.dropdown li').click(function() {
//Hide all other drop downs that are visible, and remove the class 'selected'
$(this).siblings('.selected').removeClass('selected').find('ul:visible');
//Show/Hide dropdowns
$(this).toggleClass('selected');
$('ul:first', this).stop(true, true).slideToggle('fast');
});