JSFiddle - React, Tailwind, and code Playground

HTML

<body>

  <div id="button" class="button">
    <div></div>
    <div></div>
    <div></div>
  </div>
  <div id="menu" class="none">
    <nav>
      <ul>
        <li class="menu-item">
          <a href="file:///Users/scatman01/Desktop/Code/AOS3.0/AOS-Homepage.html" class="link">Home</a>
        </li>
        <li class="menu-item">
          <a href="file:///Users/scatman01/Desktop/Code/AOS3.0/AOS-Adventures.html" class="link">Adventures</a>
        </li>
        <li class="menu-item">
          <a href="file:///Users/scatman01/Desktop/Code/AOS3.0/AOS-Trail%20Reports.html" class="link">Trail Reports</a>
        </li>
        <li class="menu-item">
          <a href="file:///Users/scatman01/Desktop/Code/AOS3.0/AOS-Reviews.html" class="link">Reviews</a>
        </li>
        <li class="menu-item">
          <a href="file:///Users/scatman01/Desktop/Code/AOS3.0/AOS-about%20me.html" class="link">About</a>
        </li>
        <li class="menu-item">
          <a href="file:///Users/scatman01/Desktop/Code/AOS3.0/AOS-Gallery.html" class="link">Gallery</a>
        </li>
        <li class="menu-item">
          <a href="file:///Users/scatman01/Desktop/Code/AOS3.0/AOS-Contact.html" class="link"><i class="fa fa-envelope"></i></a>
        </li>
      </ul>
    </nav>
  </div>
  <div id="shadow" class="none"></div>


  <div class="title">

    <h1><i class="fa fa-camera-retro"></i> The Gallery</h1>
    <p>My world as I see it.</p>
  </div>

<div class="container">
  <div class="row">
    <div class="col-lg-4 col-sm-6">
      <div class="thumbnail">
        <img src="http://www.adventuresofscatman.com/wp-content/uploads/2015/09/IMG_4276.jpg">
      </div>
    </div>
    <div class="col-lg-4 col-sm-6">
      <div class="thumbnail">
        <img src="http://www.adventuresofscatman.com/wp-content/uploads/2015/05/IMG_1174.jpg">
      </div>
    </div>
    <div class="col-lg-4 col-sm-6">
      <div class="thumbnail">
        <img...

CSS

html {
  height: 100%; 
}

body {
  height: 100%;
  margin: 0;
  padding: .1px;
  position: relative;
  background: url(http://www.adventuresofscatman.com/wp-content/uploads/2015/09/IMG_4273.jpg);
  background-size: cover;
  overflow-x: hidden;
  font-family: arvo;
}

.button{
  position: absolute;
  top: 30px;
  left: 1175px;;
  width: 45px;
  height: 50px;
}

.button div {
  height: 10%;
  border-top: 7px solid rgb(0,0,0);
  cursor: pointer;
  transition: .5s;
}

.button:hover div {
  border-color: rgb(139, 139, 139); 
}

.menu-in,
.menu-out {
  padding: .1px;
  width: 240px;
  height: 100%;
  background: rgba(0, 0, 0, .55);
  overflow: hidden;
  position: absolute;
  top: 0;
}

.menu-in {
  -webkit-animation: menu-in .9s forwards ease;
}

.menu-out{
  -webkit-animation: menu-out .4s forwards ease-in; 
}

ul {
  margin: 68px 0 0 0;
  padding: 0;
}

.menu-item {
 display: block;
  text-decoration: none;
  color: rgb(190, 190, 190);
  font: 18px/50px arial;
  text-transform: uppercase;
  height: 50px;
  text-align: center;
  transition: .1s;
}

.link {
  display: block;
  text-decoration: none;
  color: rgb(190, 190, 190);
  font: 28px/50px arial;
  text-transform: uppercase;
  height: 50px;
  text-align: center;
  transition: .1s;
}

.link:hover {
  color: rgb(230, 230, 230);
  background: rgba(200, 200, 200, .1); 
}

.shadow-in,
.shadow-out{
  width: 100%;
  height: 100%;
  position: absolute;
  top: 0;
  background: rgba(0, 0, 0, .4);
}

.shadow-in {
  -webkit-animation: shadow-in .9s forwards ease;
}

.shadow-out {
   -webkit-animation: shadow-out .4s forwards ease-in;
}

.none {
  display: none;
}

@-webkit-keyframes menu-in {
  0% {
    right: -240px;
  }
  100% {
    right: 0;
  }
}

@-webkit-keyframes menu-out {
  0% {
    right: 0;
  }
  100% {
    right: -240px;
  }
}  

@-webkit-keyframes shadow-in {
  0% {
    right: 0;
    opacity: 0;
  }
  100% {
    right: 240px;
    opacity: 1;
  }
}

@-webkit-keyframes shadow-out {
  0% {
    right: 240px;
   ...

JavaScript

document.getElementById('button').addEventListener('click', function() {
    showMenu();
});

document.getElementById('menu').addEventListener('click', function() {
    showMenu();
});

function showMenu() {
    console.log('click');
    var menu = document.getElementById('menu');
    var shadow = document.getElementById('shadow');
    var button = document.getElementById('button');
    
    menu.className = 'menu-in';
    shadow.className = 'shadow-in';
    button.className = 'none';
}

document.getElementById('shadow').addEventListener('click', function() {
    var menu = document.getElementById('menu');
    var shadow = document.getElementById('shadow');
    var button = document.getElementById('button');
    
    menu.className = 'menu-out';
    shadow.className = 'shadow-out';
    button.className = 'button';
});