Here is an amazing animated share button which is created with html and css only from Darkcode. Just click on the button Run Pen below, to see how it works:
Note: This project also use Font Awesome for creating icons.
How to create an animated share button
Step 1: Add Html
<div class="share-button">
  <span><i class="fas fa-share-alt"></i> Share!</span>
  <a href="#"><i class="fab fa-facebook-f"></i></a>
  <a href="#"><i class="fab fa-twitter"></i></a>
  <a href="#"><i class="fab fa-instagram"></i></a>
  <a href="#"><i class="fab fa-linkedin-in"></i></a>
</div>Step 2: Add CSS
body {
  margin: 0;
  padding: 0;
  font-family: 'montserrat', sans-serif;
  background: #f1f1f1;
  display: flex;
  height: 100vh;
  align-items: center;
  justify-content: center;
}
.share-button {
  width: 280px;
  height: 80px;
  background: #dfe6e9;
  border-radius: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  position: relative;
  cursor: pointer;
  transition: 0.3s linear;
}
.share-button:hover {
  transform: scale(1.1);
}
.share-button span {
  position: absolute;
  width: 100%;
  height: 100%;
  background: #2d3436;
  color: #f1f1f1;
  text-align: center;
  line-height: 80px;
  z-index: 999;
  transition: 0.6s linear;
  border-radius: 40px;
}
.share-button:hover span {
  transform: translateX(-100%);
  transition-delay: 0.3s;
}
.share-button a {
  flex: 1;
  font-size: 26px;
  color: #2d3436;
  text-align: center;
  transform: translateX(-100%);
  opacity: 0;
  transition: 0.3s linear;
}
.share-button:hover a {
  opacity: 1;
  transform: translateX(0);
}
.share-button a:nth-of-type(1) {
  transition-delay: 1s;
}
.share-button a:nth-of-type(2) {
  transition-delay: 0.8s;
}
.share-button a:nth-of-type(3) {
  transition-delay: 0.6s;
}
.share-button a:nth-of-type(4) {
  transition-delay: 0.4s;
}