Apple Liquid Glass Spinner

<!-- SVG Filter for Glass Distortion -->
<svg style="display: none">
  <filter id="glass-distortion">
    <feTurbulence type="turbulence" baseFrequency="0.008" numOctaves="2" result="noise" />
    <feDisplacementMap in="SourceGraphic" in2="noise" scale="77" />
  </filter>
</svg>

<div class="glass-spinner">
  <div class="glass-filter"></div>
  <div class="glass-overlay"></div>
  <div class="glass-specular"></div>
  <div class="glass-content">
    <div class="spinner-ring"></div>
    <div class="spinner-core"></div>
  </div>
</div>

/* Glass Spinner Container */
.glass-spinner {
  --bg-color: rgba(255, 255, 255, 0.25);
  --highlight: rgba(255, 255, 255, 0.75);
  --spinner-size: 80px;
  --ring-size: 64px;
  --core-size: 24px;
  
  position: relative;
  width: var(--spinner-size);
  height: var(--spinner-size);
  border-radius: 50%;
  overflow: hidden;
  background: transparent;
}

.glass-filter,
.glass-overlay,
.glass-specular {
  position: absolute;
  inset: 0;
  border-radius: inherit;
}

.glass-filter {
  z-index: 1;
  backdrop-filter: blur(4px);
  filter: url(#glass-distortion) saturate(120%) brightness(1.15);
}

.glass-overlay {
  z-index: 2;
  background: var(--bg-color);
}

.glass-specular {
  z-index: 3;
  box-shadow: inset 1px 1px 1px var(--highlight);
}

.glass-content {
  position: relative;
  z-index: 4;
  width: 100%;
  height: 100%;
  display: flex;
  justify-content: center;
  align-items: center;
}

.spinner-ring {
  position: absolute;
  width: var(--ring-size);
  height: var(--ring-size);
  border: 2px solid transparent;
  border-top-color: rgba(255, 255, 255, 0.8);
  border-right-color: rgba(255, 255, 255, 0.6);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

.spinner-core {
  width: var(--core-size);
  height: var(--core-size);
  background: rgba(255, 255, 255, 0.9);
  border-radius: 50%;
  animation: pulse 1s ease-in-out infinite alternate;
}

@keyframes spin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

@keyframes pulse {
  from {
    transform: scale(0.8);
    opacity: 0.5;
  }
  to {
    transform: scale(1);
    opacity: 0.8;
  }
}

/* Dark mode styles */
@media (prefers-color-scheme: dark) {
  .glass-spinner {
    --bg-color: rgba(0, 0, 0, 0.25);
    --highlight: rgba(255, 255, 255, 0.15);
  }
}