A CSS Neon Link design for UI

neonlink_ui.html

<div class="container">
  <ul class="list">
    <li class="list__item--yellow">
        <span>Home</span>
    </li>
    <li class="list__item--blue">
        <span>About us</span>
    </li>
    <li class="list__item--red">
        <span>Contact</span>
    </li>
  </ul>
</div>

</style>
body {
  display: table;
  width: 100%;
  height: 100vh;
  margin: 0;
  background: #222;
  font-family: 'Roboto Condensed', sans-serif;
  font-size: 26px;
  font-weight: 600;
  letter-spacing: 5px;
  text-transform: uppercase;
}

.container {
  display: table-cell;
  vertical-align: middle;
  text-align: center;
  width: 600px;
}

.list {
  list-style: none;
  margin: 0;
  padding: 0;
}

li {
  display: inline-block;
  padding: 0 20px;
}

span {
  position: relative;
  display: block;
  cursor: pointer;
}

.list__item--yellow {
  color: #FFC56C;
}

.list__item--blue {
  color: #6EC5E9;
}

.list__item--red {
  color: #FF5959;
}

span {
  &:before, &:after {
    content: '';
    position: absolute;
    width: 0%;
    height: 4px;
    bottom: -2px;
    margin-top: -0.5px;
    background: #fff;
  }

  &:before {
    left: -2.5px;
  }

  &:after {
    right: 2.5px;
    background: #fff;
    transition: width 0.8s cubic-bezier(0.22, 0.61, 0.36, 1);
  }

  &:hover {
    &:before {
      background: #fff;
      width: 100%;
      transition: width 0.5s cubic-bezier(0.22, 0.61, 0.36, 1);
    }

    &:after {
      background: transparent;
      width: 100%;
      transition: 0s;
    }
  }
}
</style>
<div class="container">
  <ul class="list">
    <li class="list__item--yellow">
        <span>Home</span>
    </li>
    <li class="list__item--blue">
        <span>About us</span>
    </li>
    <li class="list__item--red">
        <span>Contact</span>
    </li>
  </ul>
</div>