The light-level CSS media feature can be used to test the ambient light level.

Syntax

dim
The device is used in a dim environment, where excessive contrast and brightness would be distracting or uncomfortable to the reader. For example: night time, or a dimly illuminated indoor environment.
normal
The device is used in a environment with a light level in the ideal range for the screen, and which does not necessitate any particular adjustment.
washed
The device is used in an exceptionally bright environment, causing the screen to be washed out and difficult to read. For example: bright daylight.

Example

This code will likely not work on any devices (device compatablility is low).

@media (light-level: normal) {
  p {
    background: url("texture.jpg");
    color: #333;
  }
}

@media (light-level: dim) {
  p {
    background: #222;
    color: #ccc;
  }
}

@media (light-level: washed) {
  p {
    background: white;
    color: black;
    font-size: 2em;
  }
}

Specifications

Specification Status Comment
Unknown
The definition of 'light-level' in that specification.
Unknown Initial definition.

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic support
ExperimentalNon-standard
Chrome No support NoEdge ? Firefox No support NoIE No support NoOpera No support NoSafari No support NoWebView Android No support NoChrome Android No support NoEdge Mobile ? Firefox Android No support NoOpera Android No support NoSafari iOS No support NoSamsung Internet Android ?

Legend

No support  
No support
Compatibility unknown  
Compatibility unknown
Experimental. Expect behavior to change in the future.
Experimental. Expect behavior to change in the future.
Non-standard. Expect poor cross-browser support.
Non-standard. Expect poor cross-browser support.

Document Tags and Contributors

Contributors to this page: mfluehr, connorshea, carlosvigil, CKH4, Sebastianz, kscarfone, cvrebert
Last updated by: mfluehr,