<ul class="menu">
  <li>
    <a href="#0">
      About
      <span class="border border-top"></span>
      <span class="border border-right"></span>
      <span class="border border-bottom"></span>
      <span class="border border-left"></span>
    </a>
  </li>
  <li>
    <a href="#0">
      Projects
      <span class="border border-top"></span>
      <span class="border border-right"></span>
      <span class="border border-bottom"></span>
      <span class="border border-left"></span>
    </a>
  </li>
  <li>
    <a href="#0">
      Clients
      <span class="border border-top"></span>
      <span class="border border-right"></span>
      <span class="border border-bottom"></span>
      <span class="border border-left"></span>
    </a>
  </li>
  <li>
    <a href="#0">
      Contact
      <span class="border border-top"></span>
      <span class="border border-right"></span>
      <span class="border border-bottom"></span>
      <span class="border border-left"></span>
    </a>
  </li>
</ul>
<hr>
<ul class="menu" data-animation="diagonal">
  <li>
    <a href="#0">
      About
      <span class="border border-top"></span>
      <span class="border border-right"></span>
      <span class="border border-bottom"></span>
      <span class="border border-left"></span>
    </a>
  </li>
  <li>
    <a href="#0">
      Projects
      <span class="border border-top"></span>
      <span class="border border-right"></span>
      <span class="border border-bottom"></span>
      <span class="border border-left"></span>
    </a>
  </li>
  <li>
    <a href="#0">
      Clients
      <span class="border border-top"></span>
      <span class="border border-right"></span>
      <span class="border border-bottom"></span>
      <span class="border border-left"></span>
    </a>
  </li>
  <li>
    <a href="#0">
      Contact
      <span class="border border-top"></span>
      <span class="border border-right"></span>
      <span class="border border-bottom"></span>
      <span class="border border-left"></span>
    </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;
  --transition-duration: 0.3s;
  --transition-delay: 0.2s;
  --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;
}

.menu .border {
  position: absolute;
  left: 0;
  background: currentColor;
  transition: transform var(--transition-duration) ease-in-out;
}

.menu .border-top,
.menu .border-bottom {
  width: 100%;
  height: 1px;
  transform: scaleX(0);
}

.menu .border-left,
.menu .border-right {
  width: 1px;
  height: 100%;
  transform: scaleY(0);
}

.menu .border-top,
.menu .border-left,
.menu .border-right {
  top: 0;
}

.menu .border-bottom {
  bottom: 0;
  transform-origin: bottom right;
}

.menu .border-top {
  transform-origin: top left;
}

.menu .border-left {
  transform-origin: bottom left;
}

.menu .border-right {
  left: auto;
  right: 0;
  transform-origin: top right;
}

.menu a:hover .border-top,
.menu a:hover .border-bottom {
  transform: scaleX(1);
}

.menu a:hover .border-left,
.menu a:hover .border-right {
  transform: scaleY(1);
}

.menu a:hover .border-right {
  transition-delay: var(--transition-delay);
}

.menu a:hover .border-bottom {
  transition-delay: calc(var(--transition-delay) * 2);
}

.menu a:hover .border-left {
  transition-delay: calc(var(--transition-delay) * 3);
}


/* ANIMATIONS
–––––––––––––––––––––––––––––––––––––––––––––––––– */
.menu[data-animation="diagonal"] .border-left {
  transform-origin: top left;
}

.menu[data-animation="diagonal"] .border-right,
.menu[data-animation="diagonal"] .border-bottom {
  transform-origin: bottom right;
}

.menu[data-animation="diagonal"] a:hover [class^=border]{
  transition-delay: 0s;
}


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

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

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.