<div class="bars">
  <div class="bar"></div>
  <div class="bar"></div>
  <div class="bar"></div>
  <div class="bar"></div>
  <div class="bar"></div>
</div>

.bars {
  display: flex;
  align-items: flex-end;
  gap: 5px;
  height: 40px;
}
.bar {
  width: 10px;
  border-radius: 3px 3px 0 0;
  background: #7c6cff;
  animation: bars 1s ease-in-out infinite;
}
.bar:nth-child(1) {
  height: 20%;
  animation-delay: 0s;
}
.bar:nth-child(2) {
  height: 50%;
  animation-delay: 0.15s;
}
.bar:nth-child(3) {
  height: 80%;
  animation-delay: 0.3s;
}
.bar:nth-child(4) {
  height: 60%;
  animation-delay: 0.45s;
}
.bar:nth-child(5) {
  height: 35%;
  animation-delay: 0.6s;
}
@keyframes bars {
  0%,
  100% {
    opacity: 0.25;
  }
  50% {
    opacity: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  .bars,
  .bars * {
    animation: none !important;
  }
}