JSFiddle - React, Tailwind, and code Playground

HTML

<nav class="header">
      <input class="menu-btn" type="checkbox" id="menu-btn" />
      <label class="menu-icon" for="menu-btn"><span class="navicon"></span></label>
      <ul class="menu">
        <li><a href="#work">Our Work</a></li>
        <li><a href="#about">About</a></li>
        <li><a href="#careers">Careers</a></li>
        <li><a href="#contact">Contact</a></li>
      </ul>
    </nav>
<figure id="main-img"></figure>

CSS

body {
  width:100%;
  margin:0;
}

figure#main-img {
	width: 100%;
	position: relative;
  float:left;
	overflow: hidden;
	border-top: 1px solid #000000;
	border-bottom: 1px solid #000000;
  height: 300px;
  background-color: red;
  margin:58px 0 0 0;
}

nav.header {
	background-color: silver;
  opacity: 0.75;
  position: absolute;
  width: 100%;
  top:0;
  z-index:10;
  float: left;
  margin:0;
  overflow:hidden;
}
.header ul {
	list-style: none; 
	position: relative; 
	float: left; 
	display: block; 
	left: 50%;
	max-width: 1200px;
	margin: 0;
	padding: 0;
}
.header ul li {
	position: relative; 
	right: 50%;
}
.header li a {
	display: block;
	padding: 1em;
	text-decoration: none;
	color: #000000;
}
.header li a:hover {
	background-color: #B5B5B5;
}
.header .menu {
	clear: both;
	max-height: 0;
	transition: max-height .2s ease-out;
}
.header .menu-icon {
	cursor: pointer;
	display: inline-block;
	float: right;
	padding: 28px 20px;
	position: relative;
	user-select: none;
}
.header .menu-icon .navicon {
	background: #333;
	display: block;
	height: 2px;
	position: relative;
	transition: background .2s ease-out;
	width: 18px;
}
.header .menu-icon .navicon:before, .header .menu-icon .navicon:after {
	background: #333;
	content: '';
	display: block;
	height: 100%;
	position: absolute;
	transition: all .2s ease-out;
	width: 100%;
}
.header .menu-icon .navicon:before {
	top: 5px;
}
.header .menu-icon .navicon:after {
	top: -5px;
}
.header .menu-btn {
	display: none;
}
.header .menu-btn:checked ~ .menu {
	max-height: 240px;
}
.header .menu-btn:checked ~ .menu-icon .navicon {
	background: transparent;
}
.header .menu-btn:checked ~ .menu-icon .navicon:before {
	transform: rotate(-45deg);
}
.header .menu-btn:checked ~ .menu-icon .navicon:after {
	transform: rotate(45deg);
}
.header .menu-btn:checked ~ .menu-icon:not(.steps) .navicon:before, .header .menu-btn:checked ~ .menu-icon:not(.steps) .navicon:after {
	top: 0;
}

@media only screen and (min-width: 750px) {
.header li...