JSFiddle - React, Tailwind, and code Playground

HTML

<div class="product-type">
  	<ul>
  		<li class="slide__title selected">Cars</li>
  		<li class="slide__title" >Motorcycles</li>
  		<li class="slide__title">Power Equiptment</li>
  		<li class="slide__title">Marine</li>
  	</ul>
  </div>

	<ul id="slides">
		<li class="slide cars"></li>
		<li class="slide bikes"></li>
		<li class="slide mower"></li>	
		<li class="slide boat"></li>
	</ul>

SCSS

/*
essential styles:
these make the slideshow work
*/

.corporatelanding {
	position: relative;
	height: 100%;
	width: 100%;
	overflow: hidden;
}
.right-slide {
	position: absolute; 
	top: 0; 
	right:0;
	height: 100vh;
	z-index:1000;
	background-color: #fff;
	transition: all 1s; 
	left: 98%;

	.content { 
		opacity: 0; 
		transition: all 1s;
		width: 80%;
		margin-left: auto;
		margin-right: auto;
		min-width: 500px; 
		margin-top: 500px;

	}

	&:hover {
		left: 60px;


		.content { 
			opacity: 1;
			transition-delay: .5s;
			margin-top: 200px;
		}
	}
}
#slides {
    position: relative;
    padding: 0px;
    margin: 0px;
    list-style-type: none;
    height: 100vh;
}

.slide {
    position: absolute;
    left: 0px;
    top: 0px;
 	bottom: 0;
 	right: 0;
    opacity: 0;
    z-index: 1;

    -webkit-transition: opacity 5s;
    -moz-transition: opacity 5s;
    -o-transition: opacity 5s;
    transition: opacity 5s;
    
    transition-delay: 2s;
	background-repeat: no-repeat;
	background-size: cover;
	content: " ";

    &.cars {
		background-image: url("http://www.honda.com.au/content/dam/honda/galleries/homepage/Honda-Civic-Landing.jpg");
		background-color: #333;
	}

	&.bikes {
		background-image: url("http://www.honda.com.au/content/dam/honda/galleries/homepage/Jet.jpg");
		background-color: #ccc;
	}

	&.mower { 
		background-image: url("http://www.honda.com.au/content/dam/honda/galleries/homepage/Lawnmower.jpg");
		background-color: #cec;
	}

	&.boat {
		background-image: url("http://www.honda.com.au/content/dam/honda/galleries/homepage/Boat.jpg");
		background-color: #fff;
	}
}

.showing {
    opacity: 1;
    z-index: 2;
    transition: opacity 2s;
    color: white!important;
}

.selected {
	color: white!important;
}

.product-type {
	position: absolute; 
	top: 20%; 
	color: white; 
	font-size: 60px;
	font-weight: bold;
	z-index: 4;
	left: 10%;

	ul {
		margin: 0;
		padding: 0;
		width: 100%;
		height: 100%
	}

	li {
		list-style-type: none;
		margin:...

JavaScript

var slide_titles = document.querySelectorAll('.slide__title');
var slide_background = document.querySelectorAll('.slide');


function removeSelected() {
  for(var i = 0; i < slide_titles.length; i++) {
    if(slide_titles[i].className.indexOf('selected') != -1) {
      console.log("remove");
      slide_titles[i].classList.remove("selected");
    }
  }
}


var clickEvent = function(index) {
slide_titles[index].addEventListener("click", () => {
        removeSelected();
        slide_background[index].classList.add("show");
        slide_titles[index].classList.add("selected");
        console.log(slide_background[index]);

  });
}


   for(var i = 0; i < slide_titles.length; i++) {
      clickEvent(i);
   }