body {
  margin: 0;
  padding: 0;
  background: #262626;
}

ul {
  display: flex;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
}

ul li {
  list-style: none;
}

ul li span {
  width: 80px;
  height: 80px;
  background-color: #fff;
  text-align: center;
  line-height: 80px;
  font-size: 35px;
  margin: 0 10px;
  display: block;
  border-radius: 50%;
  position: relative;
  overflow: hidden;
  border: 3px solid #fff;
  z-index: 1;
}

ul li span:before {
  content: "";
  position: absolute;
  top: 100%;
  left: 0;
  width: 100%;
  height: 100%;
  transition: 0.5s;
  z-index: 2;
}

ul li span:hover:before {
  top: 0;
}

ul li:nth-child(1) span:before {
  background: #3b5999;
}

ul li:nth-child(2) span:before {
  background: #55acee;
}

ul li:nth-child(3) span:before {
  background: #0077b5;
}

ul li:nth-child(4) span:before {
  background: #dd4b39;
}