# Mica

> An opaque window backdrop that samples the desktop wallpaper and blends it subtly with a layer of system colour, tinting the app to match its context.

- Category: Platform-native
- Era: 2021 – present
- Origin: Microsoft Windows 11 Fluent Design System
- Lesson: https://design.dawit.dev/styles/mica
- Try it: https://design.dawit.dev/styles/mica?style=mica

## Where it came from

Mica is a Microsoft material introduced in Windows 11 as part of the Fluent Design System update. Unlike Acrylic (a translucent blur of the content immediately behind it), Mica is opaque and samples only the desktop wallpaper, once — creating a calmer tint that reflects the wallpaper under the window and falls back to a neutral colour when the app is inactive. It gives Windows 11 apps a sense of belonging to the system while remaining readable.

## How to spot it

- Opaque backdrop tinted by the desktop wallpaper
- Falls back to a solid neutral colour when the window is inactive
- Two variants — Mica and the stronger-tinted Mica Alt — as the base layer under content layers
- Responds to system light and dark mode

## Strengths

- Connects app to system context without full transparency
- More legible than fully transparent Acrylic
- Distinctive Windows 11 personality

## Weaknesses

- Requires WinUI 3 / WinAppSDK — not available on web
- Tint quality depends on wallpaper colour — can look muddy
- Subtle effect easy to miss on static screenshots

## In the wild

- Windows 11 Settings application
- Microsoft Store and Xbox apps on Windows 11
- Windows 11 File Explorer window chrome

## Use it when

Windows 11 desktop apps using WinUI 3, or web UIs evoking a Windows 11 native feeling.

## Related styles
[Fluent Design](https://design.dawit.dev/styles/fluent.md), [Glassmorphism](https://design.dawit.dev/styles/glassmorphism.md), [Frosted Acrylic](https://design.dawit.dev/styles/frosted-acrylic.md)