* { box-sizing: border-box; }
body {
  background: #0f172a;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

.audio-wave {
  display: flex;
  align-items: center;
  gap: 6px;
  height: 60px;
}

.audio-wave span {
  display: block;
  width: 6px;
  height: 100%;
  background: #3b82f6;
  border-radius: 50px;
  animation: wave 1.2s ease-in-out infinite;
}

/* Vary animation delays and durations for randomness */
.audio-wave span:nth-child(1) { animation-duration: 0.8s; height: 40%; }
.audio-wave span:nth-child(2) { animation-duration: 1.1s; height: 70%; }
.audio-wave span:nth-child(3) { animation-duration: 1.3s; height: 100%; }
.audio-wave span:nth-child(4) { animation-duration: 0.9s; height: 60%; }
.audio-wave span:nth-child(5) { animation-duration: 1.0s; height: 50%; }

@keyframes wave {
  0%, 100% { transform: scaleY(0.5); background: #3b82f6; }
  50% { transform: scaleY(1); background: #60a5fa; }
}