* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  width: 100%;
  min-height: 100vh;
  display: grid;
  place-items: center;
  background-color: rgba(253, 251, 251);
}
ul {
  display: flex;
  border-bottom: 15px solid rgb(4, 32, 114);
  border-radius: 10px;
}
ul li {
  width: 40px;
  height: 40px;
  list-style: none;
  background-color: royalblue;
  margin: auto 20px;
  border-radius: 50%;
  animation: bouncing 1s linear infinite alternate-reverse;
}
@keyframes bouncing {
  0% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-150px);
  }
  100% {
    transform: translateY();
  }
}
  ul li:nth-child(2) {
    animation-delay: 0.2s;
  }
  ul li:nth-child(3) {
    animation-delay: 0.4s;
  }
  ul li:nth-child(4) {
    animation-delay: 0.6s
  }
  ul li:nth-child(5) {
    animation-delay: 0.8s;
  }