JSFiddle - React, Tailwind, and code Playground

by deadlyicon

HTML

<ul>
    <li>one</li>
    <li>two</li>
    <li>three</li>
</ul>

CSS

li.strong{
    font-weight: bold
}

JavaScript

jQuery.fn.isEmpty = function() {
    return this.length === 0;
  };

  jQuery.fn.isPresent = function() {
    return !this.isEmpty();
  };
  
  jQuery.fn.or = function(other) {
    if (this.isPresent()) return this;
    if ($.isFunction(other)) return other.call(this);
    return other;
  };

setInterval(function(){
    
    $('li.strong').or($('li:last'))
        .removeClass('strong')
        .next().or(function(){ return $('li:first'); })
        .addClass('strong');
    
},1000);