Social media icon

<link href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.1.1/css/all.min.css" rel="stylesheet">
 
  <ul>
    <li><a href="#"><i class="fa-brands fa-instagram instagram"></i></a></li>
    <li><a href="#"><i class="fa-brands fa-whatsapp whatsapp"></i></a></li>
    <li><a href="#"><i class="fa-brands fa-twitter twitter"></i></a></li>
</ul>

*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  background: #000;
}

ul {
  position: relative;
  display: flex;
}
ul li {
  position: relative;
  list-style: none;
  margin: 0 20px;
  cursor: pointer;
}
ul li a {
  text-decoration: none;
}
ul li a .fa-brands {
  font-size: 6em;
  color: #222;
}
ul li a::before {
  font-family: "FontAwesome";
  position: absolute;
  top: 0;
  left: 0;
  font-size: 6em;
  height: 0;
  overflow: hidden;
  transition: 0.5s ease-in-out;
}

ul li:nth-child(1) a::before {
  content: "\f16d";
  background-image: linear-gradient(45deg, 
    #f09433 0%,#e6683c 25%,#dc2743 50%,#cc2366 75%,
    #bc1888 100%);
  -webkit-background-clip: text;
   -webkit-text-fill-color: transparent;
  border-bottom: 4px solid #dc2743;
}
ul li:nth-child(2) a::before {
  content: "\f232";
  color: #25D366;
  border-bottom: 4px solid #25D366;
}
ul li:nth-child(3) a::before {
  content: "\f099";
  color: #1DA1F2;
  border-bottom: 4px solid #1DA1F2;
}
ul li:hover a::before {
  height: 100%;
}