# Modern UI Effects Research (2025-2026)

## Liquid Glass (Apple WWDC 2025)
Evolved glassmorphism with directional lighting. Three-layer approach: highlight, shadow, illumination.
- `backdrop-filter: blur(20px) saturate(1.5)` — higher saturation than basic glass
- `inset 0 1px 0 rgba(255,255,255,0.15)` — top highlight (light direction)
- `inset 0 -1px 0 rgba(0,0,0,0.1)` — bottom shadow
- Outer drop shadow for depth: `0 8px 32px rgba(0,0,0,0.3)`
- Advanced: SVG `feTurbulence` + `feSpecularLighting` for refraction (Chromium only)
- Browser support: `backdrop-filter` ~88%, Firefox since v103

## Aurora / Gradient Mesh Backgrounds
Stacked animated radial gradients simulating northern lights. Pairs well with glass cards on dark backgrounds.
- Multiple `radial-gradient(ellipse ...)` layers with partial opacity
- Animated via `background-position` shift (GPU-friendly)
- `@property` rule enables direct gradient color animation (broad support since 2024)
- Best for ambient background movement, not for content areas

## Animated Glow Borders
Rotating `conic-gradient` borders with blur halo. Striking on dark backgrounds.
- Outer wrapper with `conic-gradient(from var(--angle), color1, color2, color3, color1)`
- `::before` pseudo with `filter: blur(12px)` and `opacity: 0.5` for glow halo
- `@property --angle` trick to animate custom property inside `conic-gradient`
- Use sparingly — best for single highlight elements (FAB, CTA), not all cards

## Modern Neumorphism (2025-2026 revision)
Subtler than the original trend. Higher contrast, less extreme extrusion, combined with accent colors.
- Light and dark shadow pair: `6px 6px 12px rgba(0,0,0,0.5)` + `-6px -6px 12px rgba(60,50,80,0.15)`
- `border: 1px solid rgba(255,255,255,0.05)` for definition
- Works on dark backgrounds with slightly lighter "uplift" shadow direction
- Better suited for interactive elements (buttons, toggles) than content cards

## Sources
- Apple Liquid Glass CSS: dev.to/gruszdev, dev.to/kevinbism, css-tricks.com, kube.io
- Aurora: dev.to/oobleck, daltonwalsh.com, github.com/mattnewdavid
- Glow borders: frontendmasters.com (Kevin Powell), docode.co.in
- Trends overview: medium.com/design-bootcamp, index.dev, bighuman.com
