div.switch-button
	span.active
	button.switch-button-case.left.active-case Pizza
	button.switch-button-case.right Pasta
	
a(class='signature', href='http://vanderlanth.io' target='_blank') Made with ♥ by vanderlanth
View Compiled
* {
	margin: 0;
	padding: 0;
}

html, body {
	height: 100vh;
	width: 100vw;
	background-color: #151515;
}

.switch-button{
	width: 400px;
	height: 40px;
	text-align: center;
	position: absolute;
	left: 50%;
	top: 50%;
	transform: translate3D(-50%, -50%, 0);
	will-change: transform;
	z-index: 197 !important;
	cursor: pointer;
	transition: .3s ease all;
	border: 1px solid white;
	&-case{
		display: inline-block;
		background: none;
		width: 49%;
		height: 100%;
		color: white;
		position: relative;
		border: none;
		transition: .3s ease all;
		text-transform: uppercase;
		letter-spacing: 5px;
		padding-bottom: 1px;
		&:hover{
			color: grey;
			cursor: pointer;
		}
		&:focus {
			outline: none;
		}
	}
	.active {
		color: #151515;
		background-color: white;
		position: absolute;
		left: 0;
		top: 0;
		width: 50%;
		height: 100%;
		z-index: -1;
		transition: .3s ease-out all;
		&-case{
			color: #151515;
		}
	}
}

.signature {
	position: fixed;
  font-family:  sans-serif;
	font-weight: 100;
	bottom: 10px;
	left: 0;
	letter-spacing: 4px;
	font-size: 10px;
	width: 100vw;
  text-align: center;
  color: white;
	text-transform: uppercase;
  text-decoration: none;
}
View Compiled
'use strict';

var switchButton 			= document.querySelector('.switch-button');
var switchBtnRight 			= document.querySelector('.switch-button-case.right');
var switchBtnLeft 			= document.querySelector('.switch-button-case.left');
var activeSwitch 			= document.querySelector('.active');

function switchLeft(){
	switchBtnRight.classList.remove('active-case');
	switchBtnLeft.classList.add('active-case');
	activeSwitch.style.left 						= '0%';
}

function switchRight(){
	switchBtnRight.classList.add('active-case');
	switchBtnLeft.classList.remove('active-case');
	activeSwitch.style.left 						= '50%';
}

switchBtnLeft.addEventListener('click', function(){
	switchLeft();
}, false);

switchBtnRight.addEventListener('click', function(){
	switchRight();
}, false);

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.