ul {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: rotate(45deg) translate(-50%, -50%);
}

li {
  list-style-type: none;
  position: absolute;
  top: 0px;
  left: 0px;
  width: 20px;
  height: 20px;
  background: #f5d4a1;
  border-radius: 50%;
}

#a {
  animation: a 1s ease-in-out infinite;
  top: -40px;
  left: -40px;
}

#b {
  animation: b 1s ease-in-out infinite;
  top: -40px;
  left: 0px;
}

#c {
  animation: c 1s ease-in-out infinite;
  top: -40px;
  left: 40px;
}

#d {
  animation: d 1s ease-in-out infinite;
  top: 0px;
  left: -40px;
}

#e {
  animation: e 1s ease-in-out infinite;
  top: 0px;
  left: 0px;
}

#f {
  animation: f 1s ease-in-out infinite;
  top: 0px;
  left: 40px;
}

#g {
  animation: g 1s ease-in-out infinite;
  top: 40px;
  left: -40px;
}

#h {
  animation: h 1s ease-in-out infinite;
  top: 40px;
  left: 0px;
}

#i {
  animation: i 1s ease-in-out infinite;
  top: 40px;
  left: 40px;
}

@keyframes a {
  50% {
    top: 0px;
    left: -40px;
  }
  100% {
    top: 0px;
    left: -40px;
  }
}
@keyframes b {
  50% {
    top: -40px;
    left: -40px;
  }
  100% {
    top: -40px;
    left: -40px;
  }
}
@keyframes c {
  50% {
    top: -40px;
    left: 0px;
  }
  100% {
    top: -40px;
    left: 0px;
  }
}
@keyframes d {
  50% {
    top: 40px;
    left: -40px;
  }
  100% {
    top: 40px;
    left: -40px;
  }
}
@keyframes f {
  50% {
    top: -40px;
    left: 40px;
  }
  100% {
    top: -40px;
    left: 40px;
  }
}
@keyframes g {
  50% {
    top: 40px;
    left: 0px;
  }
  100% {
    top: 40px;
    left: 0px;
  }
}
@keyframes h {
  50% {
    top: 40px;
    left: 40px;
  }
  100% {
    top: 40px;
    left: 40px;
  }
}
@keyframes i {
  50% {
    top: 0px;
    left: 40px;
  }
  100% {
    top: 0px;
    left: 40px;
  }
}