JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
	<h1>LIST<i class="fa fa-plus" aria-hidden="true"></i></h1>
	<input type="text" placeholder="Add New Todo">
</div>

<script src="https://use.fontawesome.com/8ee899078b.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.2.4/jquery.js"></script>

CSS

body {
	font-family: 'Roboto';
	background: #780206;  /* fallback for old browsers */
	background: -webkit-linear-gradient(to right, #061161, #780206);  /* Chrome 10-25, Safari 5.1-6 */
	background: linear-gradient(to right, #061161, #780206); /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
	
}

.fa-plus {
	float: right;
}

#container {
	margin: 100px auto;
	width: 360px;
	background-color: #f7f7f7;
	box-shadow: 0 0 3px rgba(0, 0, 0, 0.1)
}

h1	{
	background-color: #2980b9;
	color: white;
	margin: 0;
	padding: 10px 20px;
	font-size: 24px;
	font-weight: normal;
}

input {
	width: 100%;
	font-size: 18px;
	background-color: #f7f7f7;
	height: inherit;
	padding: 13px 13px 13px 20px;
	box-sizing: border-box;
	color: #2980b9;
	border: 3px solid rgba(0, 0, 0, 0);
}

input:focus {
	background-color: white;
	border: 3px solid blue;
	outline: none;
}

JavaScript

var plusSign = $("h1 i")

plusSign.on("click",function(event){
	$('input:text').slideToggle(3000);
})