<ul class="menu">
  <li>
    <a href="#0" data-icon="&#xf2bb;">
      About
    </a>
  </li>
  <li>
    <a href="#0" data-icon="&#xf0ae;">
      Projects
    </a>
  </li>
  <li>
    <a href="#0" data-icon="&#xf0c0;">
      Clients
    </a>
  </li>
  <li>
    <a href="#0" data-icon="&#xf0c0;">
      Contact
    </a>
  </li>
</ul>
<hr>
<ul class="menu" data-animation="to-left">
  <li>
    <a href="#0" data-icon="&#xf2bb;">
      About
    </a>
  </li>
  <li>
    <a href="#0" data-icon="&#xf0ae;">
      Projects
    </a>
  </li>
  <li>
    <a href="#0" data-icon="&#xf0c0;">
      Clients
    </a>
  </li>
  <li>
    <a href="#0" data-icon="&#xf0c0;">
      Contact
    </a>
  </li>
</ul>
<footer class="page-footer">
  <small>Made with <span>❤</span> by <a href="http://georgemartsoukos.com/" target="_blank">George Martsoukos</a>
  </small>
</footer>

:root {
  --body-bg-color: #1a1c1d;
  --text-color: #aaaebc;
  --hr-color: #26292a;
  --timing-function: cubic-bezier(0.82, 0.2, 0.42, 1);
  --red: #e74c3c;
}

ul {
  list-style: none;
}

a {
  color: inherit;
  text-decoration: none;
}

body {
  margin: 30px 0;
  font: 22px sans-serif;
  background: var(--body-bg-color);
  color: var(--text-color);
}

hr {
  border-color: var(--hr-color);
  margin: 20px 0;
}

.menu {
  display: flex;
  justify-content: center;
}

.menu li {
  margin-right: 70px;
}

.menu a {
  position: relative;
  display: block;
  padding: 10px;
  overflow: hidden;
  transition: color 0s 0.25s var(--timing-function);
}

.menu a::before,
.menu a::after {
  position: absolute;
  left: 0;
  width: 100%;
}

.menu a::before {
  content: '';
  top: 50%;
  transform: translate(-101%, -50%);
  height: 50%;
  z-index: 1;
  background: var(--text-color);
  transition: transform 0.5s var(--timing-function);
}

.menu a::after {
  content: attr(data-icon);
  font-family: "Font Awesome 5 Free";
  font-weight: 900;
  top: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100%;
  color: var(--text-color);
  opacity: 0;
  transition: opacity 0s 0.25s var(--timing-function);
}

.menu a:hover {
  color: transparent;
}

.menu a:hover::before {
  transform: translate(101%, -50%);
}

.menu a:hover::after {
  opacity: 1;
}


/* ANIMATIONS
–––––––––––––––––––––––––––––––––––––––––––––––––– */
.menu[data-animation="to-left"] a::before {
  transform: translate(101%, -50%);
}

.menu[data-animation="to-left"] a:hover::before {
  transform: translate(-101%, -50%);
}


/* FOOTER
–––––––––––––––––––––––––––––––––––––––––––––––––– */
.page-footer {
  position: absolute;
  bottom: 10px;
  right: 10px;
  font-size: 1rem;
}

.page-footer span {
  color: var(--red);
}