.social-share a {
  display: inline-block;
  margin-right: 10px;
  font-size: 20px;
  color: #fff;
  width: 40px;
  height: 40px;
  line-height: 40px;
  text-align: center;
  border-radius: 50%;
  background-color: #4267B2; /* Facebook default */
  transition: 0.3s;
}
.social-share a:hover { opacity: 0.8; }
.social-share a:nth-child(2) { background-color: #1DA1F2; } /* Twitter */
.social-share a:nth-child(3) { background-color: #25D366; } /* WhatsApp */
.social-share a:nth-child(4) { background-color: #0077B5; } /* LinkedIn */