Build a glassmorphism or neumorphism CSS effect visually.
background: rgba(255, 255, 255, 0.25); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); border: 1px solid rgba(255, 255, 255, 0.3); border-radius: 20px;
It layers a semi-transparent background over `backdrop-filter: blur()`, which blurs whatever sits behind the element — giving a frosted-glass look. A thin, semi-transparent border helps sell the glass edge.
It uses two offset box-shadows in opposite directions — a dark one bottom-right and a light one top-left — both in a colour close to the background, which makes the element look softly extruded from (or pressed into) the surface.
It's supported in all modern browsers (Chrome, Edge, Safari, Firefox), though older browser versions may need the -webkit- prefix included in the generated code, or may ignore the blur gracefully.