Create Apple Liquid Glass UI with Pure CSS & SVG Filter

This is a CSS and SVG implementation of an Apple Liquid Glass-style UI with a realistic liquid distortion effect.

It recreates the look of frosted, distorted glass with specular highlights without the need for JavaScript.

Features:

• Multi-layered glass effect: Combines backdrop filters, displacement mapping, and specular highlights for realistic depth
• SVG-based distortion filters: Uses fractal noise and displacement mapping for organic glass textures
• CSS custom properties: Configurable colors, transparency levels, and highlight intensities
• Hardware-accelerated effects: Leverages GPU for smooth transitions and blur operations

See it in action:

How to use it:

1. Set up the HTML. The structure relies on a parent container with several nested children, each representing a different layer of the effect.

<div class="glass-container glass-container--rounded glass-container--large">
  <div class="glass-filter"></div>
  <div class="glass-overlay"></div>
  <div class="glass-specular"></div>
  <div class="glass-content glass-content--inline">
  ... Any content here ...
  </div>
</div>

2. Include this SVG filter definition in your document.

<svg style="display: none">
  <filter id="lg-dist" x="0%" y="0%" width="100%" height="100%">
    <feTurbulence type="fractalNoise" baseFrequency="0.008 0.008" numOctaves="2" seed="92" result="noise" />
    <feGaussianBlur in="noise" stdDeviation="2" result="blurred" />
    <feDisplacementMap in="SourceGraphic" in2="blurred" scale="70" xChannelSelector="R" yChannelSelector="G" />
  </filter>
</svg>

3. Define the glass appearance and the layering logic in CSS.

:root {
  --lg-bg-color: rgba(255, 255, 255, 0.25);
  --lg-highlight: rgba(255, 255, 255, 0.75);
  --lg-text: #ffffff;
  --lg-hover-glow: rgba(255, 255, 255, 0.4);
  --lg-red: #fb4268;
  --lg-grey: #5b5b5b;
}
/* ========== GLASS CONTAINER ========== */
.glass-container {
  position: relative;
  display: flex;
  font-weight: 600;
  color: var(--lg-text);
  cursor: pointer;
  background: transparent;
  border-radius: 2rem;
  overflow: hidden;
  box-shadow: 0 6px 6px rgba(0, 0, 0, 0.2), 0 0 20px rgba(0, 0, 0, 0.1);
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 2.2);
}
.glass-container--rounded {
  border-radius: 5rem;
  margin: 0.5rem;
  fill: var(--lg-grey);
}
.glass-container--small {
  margin: 5rem 0 1rem;
  border-radius: 5rem;
  text-shadow: 1px 1px 1px rgba(0, 0, 0, 0.25);
}
.glass-container--large {
  min-width: 32rem;
}
.glass-container--medium {
  min-width: 25rem;
}
.glass-container svg {
  fill: white;
}
/* ========== GLASS ITEM ========== */
.glass-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-between;
  border-radius: 1rem;
  color: white;
  transition: color 0.3s ease;
  text-align: center;
}
.glass-item svg {
  fill: white;
  height: 50px;
  margin-bottom: 0.25rem;
}
.glass-item--active {
  background: rgba(0, 0, 0, 0.25);
  color: black;
  margin: 0 -0.5rem;
  padding: 0.25rem 1.95rem;
  border-radius: 5rem;
}
.glass-item--active svg {
  fill: black;
}
/* ========== GLASS LAYERS ========== */
.glass-filter {
  position: absolute;
  inset: 0;
  z-index: 0;
  backdrop-filter: blur(0px);
  filter: url(#lg-dist);
  isolation: isolate;
}
.glass-overlay {
  position: absolute;
  inset: 0;
  z-index: 1;
  background: var(--lg-bg-color);
}
.glass-specular {
  position: absolute;
  inset: 0;
  z-index: 2;
  border-radius: inherit;
  overflow: hidden;
  box-shadow: inset 1px 1px 0 var(--lg-highlight),
    inset 0 0 5px var(--lg-highlight);
}
.glass-content {
  position: relative;
  z-index: 3;
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 1rem 1.5rem 0.9rem;
}
.glass-content--inline {
  padding: 0.25rem 2rem 0.25rem 0.75rem;
  flex: 1 1 auto;
  justify-content: space-between;
}