<nav class="nav-main">
  
  <div class="btn-toggle-nav">
    <div id='hamburger'>
      <a onclick="toggleMenu()" href="#">&#9776</a>
    </div>
  </div>
  
  <ul>
    <li><a href="#">Home</a></li>
    <li><a href="#">Portfolio</a></li>
    <li><a href="#">About Us</a></li>
    <li><a href="#">Gallery</a></li>
    <li><a href="#">Contact</a></li>
  </ul>
</nav>

<aside class="nav-sidebar">
    <ul>
      <li><span>Projects</span></li>
      <li><span>Making a Website</span></li>
      <li><span>Creating a Video</span></li>
      <li><span>SEO Optimizing a Website</span>     </li>
  </ul>
</aside>

/* http://meyerweb.com/eric/tools/css/reset/ 
   v2.0 | 20110126
   License: none (public domain)
*/

html, body, div, span, applet, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
a, abbr, acronym, address, big, cite, code,
del, dfn, em, img, ins, kbd, q, s, samp,
small, strike, strong, sub, sup, tt, var,
b, u, i, center,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td,
article, aside, canvas, details, embed, 
figure, figcaption, footer, header, hgroup, 
menu, nav, output, ruby, section, summary,
time, mark, audio, video {
  margin: 0;
  padding: 0;
  border: 0;
  font-size: 100%;
  font: inherit;
  vertical-align: baseline;
}
/* HTML5 display-role reset for older browsers */
article, aside, details, figcaption, figure, 
footer, header, hgroup, menu, nav, section {
  display: block;
}
body {
  line-height: 1;
}
ol, ul {
  list-style: none;
}
blockquote, q {
  quotes: none;
}
blockquote:before, blockquote:after,
q:before, q:after {
  content: '';
  content: none;
}
table {
  border-collapse: collapse;
  border-spacing: 0;
}

/*Start main styles*/

body {
  background-color: #d2ccd6;
}

.nav-main: {
  position: fixed;
  top: 0;
  width: 60px;
  height: 60px;
  background-color: #219797;
  display: flex;
  flex-wrap: wrap;
  z-index: 1000;
}

.btn-toggle-nav {
  width: 60px;
  height: 60px;

  background-color: #219797;
  display: flex;
}

#hamburger {
  justify-align: center;
  item-align: center;
  margin: auto;
  font-size: 2em;
}

#hamburger a {
  text-decoration: none;
  color: purple;
}

/* visited link */
#hamburger a:visited {
    color: purple;
}

/* mouse over link */
#hamburger a:hover {
    color: white;
}

/* selected link */
#hamburger a:active {
    color: white;
}

.nav-main {
  display: flex;
  background-color: white;
}

.nav-main ul li {
  display: flex;
  display-wrap: wrap;
  float: left;
  padding-left: 15px;
  list-style: none;
  line-height: 60px;
}

.nav-main ul li a {
  display: flex;
  flex-wrap: wrap;
  padding-left: 15px;
  text-decoration: none;
  color: grey;
  font-family: arial;
  font-size: 1.2em;
}

.nav-main ul li a:hover {
  color: purple;
}

.nav-sidebar {
  color: white;
  width: 50px;
  padding: 0 5px;
  height: 100vh;
  background-color: #1b1b1b;
  x-index: 1000;
  transition: all 0.3s ease-in-out;
}

.nav-sidebar ul {
  padding-top: 15px;
  overflow: hidden;
  visibility: hidden;
}

.nav-sidebar ul li {
  line-height: 60px;
}

.nav-sidebar li span, .nav-sidebar ul li a {
  display: block;
  height: 60px;
  padding: 0 10px;
  text-decoration: none;
  text-transform: uppercase;
  font-size: 16px;
  white-space: nowrap;
}

.nav-sidebar ul li a {
 background-color: #222;
}
let toggled = false;
function toggleMenu() {
  let getSidebarUl = document.querySelector('.nav-sidebar ul');
  let getSidebar = document.querySelector('.nav-sidebar');
  
  if (toggled === false) {
      getSidebar.style.width = "250px";
      getSidebarUl.style.visibility = 'visible'
      toggled = true;
  } else {
     getSidebar.style.width = "50px";
     getSidebarUl.style.visibility = 'hidden'
     toggled = false;
  }

  
  
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.