<div class="wrapper">
  <div></div>
</div>
<div class="wrapper">
  <div></div>
</div>
<div class="wrapper">
  <div></div>
</div>
<div class="wrapper">
  <div></div>
</div>
<div class="wrapper">
  <div></div>
</div>

* {
  box-sizing: border-box;
}
body {
  background: linear-gradient(to top, #a18cd1 0%, #fbc2eb 100%);
  width:100vw;
  height:100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  margin: 0;
  padding: 0;
}
.wrapper {
  position: absolute;
  animation: x 1s ease-in-out alternate infinite 0s both;
}
.wrapper:nth-of-type(2) {animation-delay: 0.1s}
.wrapper:nth-of-type(3) {animation-delay: 0.2s}
.wrapper:nth-of-type(4) {animation-delay: 0.3s}
.wrapper:nth-of-type(5) {animation-delay: 0.4s}


.wrapper>div {
  width: 50px;
  height: 50px;
  background-color: #fff;
  border-radius: 100%;
  margin: 40px;
  animation: y 1s linear infinite 0s both;
}
.wrapper:nth-of-type(2)>div {
  animation-delay: 0.1s;
  height: 40px;
  width: 40px;
  opacity: 0.8;
}
.wrapper:nth-of-type(3)>div {
  animation-delay: 0.2s;
  height: 30px;
  width: 30px;
  opacity: 0.7;
}
.wrapper:nth-of-type(4)>div {
  animation-delay: 0.3s;
  height: 20px;
  width: 20px;
  opacity: 0.5;
}
.wrapper:nth-of-type(5)>div {
  animation-delay: 0.4s;
  height: 10px;
  width: 10px;
  opacity: 0.3;
}

@keyframes x {
  0% {
    transform: translatex(-100px)
  }
  100% {
    transform: translatex(100px)
  }
}

@keyframes y {
  25% {
    transform: translatey(-50px);
  }
  0%, 50%, 100% {
    transform: translatey(0);
  }
  75% {
    transform: translatey(50px);
    
  }
}