<nav>
  <ul>
    <li><a href="http://www.pengfeixc.com" target="_blank">pengfeixc.com</a></li>
    <li><a href="http://www.weijuan.design" target="_blank">weijuan.design</a></li>
    <li><a href="http://mini.pengfeixc.com" target="_blank">mini.pengfeixc.com</a></li>
    <li><a href="http://www.pengfeixc.com/about" target="_blank">WangPF</a></li>
  </ul>
</nav>
body {
  margin: 0px;
  padding: 0px;
  background: #e74c3c;
  font-family: "Lato", sans-serif;
}

nav {
  float: none;
  clear: both;
  width: 30%;
  margin: 10% auto;
  background: #eee;
}

nav ul {
  list-style: none;
  margin: 0px;
  padding: 0px;
}

nav li {
  float: none;
  width: 100%;
}

nav li a {
  display: block;
  width: 100%;
  padding: 20px;
  border-left: 5px solid;
  position: relative;
  z-index: 2;
  text-decoration: none;
  color: #444;
  box-sizing: border-box;
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;
}

nav li a:hover {
  border-bottom: 0px;
  color: #fff;
}

nav li:first-child a {
  border-left: 10px solid #3498db;
}

nav li:nth-child(2) a {
  border-left: 10px solid #ffd071;
}

nav li:nth-child(3) a {
  border-left: 10px solid #f0776c;
}

nav li:last-child a {
  border-left: 10px solid #1abc9c;
}

nav li a:after {
  content: "";
  height: 100%;
  left: 0;
  top: 0;
  width: 0px;
  position: absolute;
  transition: all 0.3s ease 0s;
  -webkit-transition: all 0.3s ease 0s;
  z-index: -1;
}

nav li a:hover:after {
  width: 100%;
}

nav li:first-child a:after {
  background: #3498db;
}

nav li:nth-child(2) a:after {
  background: #ffd071;
}

nav li:nth-child(3) a:after {
  background: #f0776c;
}

nav li:last-child a:after {
  background: #1abc9c;
}

External CSS

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External JavaScript

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