body {
  margin: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
  font-family: verdana;
}

ul {
  padding: 0;
  display: flex;
}

li {
  list-style-type: none;
  padding: 10px 20px;
}

a {
  text-decoration: none;
  text-transform: uppercase;
  font-size: 20px;
  color: #222;
  position: relative;
}

ul li a:before {
  content: "";
  width: 0;
  height: 5px;
  background-color: #00bcd4;
  position: absolute;
  top: 120%;
  left: 0;
  transition: all 0.5s;
}

ul li a:after {
  content: "";
  width: 0;
  height: 5px;
  background-color: #f0f;
  position: absolute;
  top: 120%;
  right: 0;
  transition: all 0.5s;
}

ul li a:hover:before {
  width: 50%;
  transform: translateX(100%);
}

ul li a:hover:after {
  width: 50%;
  transform: translateX(-100%);
}