prefers-contrast CSS media featureThe prefers-contrast CSS media feature is used to detect whether the user has requested the web content to be presented with a lower or higher contrast.
no-preferenceIndicates that the user has made no preference known to the system. This keyword value evaluates as false in the Boolean context.
moreIndicates that user has notified the system that they prefer an interface that has a higher level of contrast.
lessIndicates that user has notified the system that they prefer an interface that has a lower level of contrast.
customIndicates that user has notified the system for using a specific set of colors, and the contrast implied by these colors matches neither more nor less. This value will match the color palette specified by users of forced-colors: active.
Various operating systems do support such preferences and user agents are likely to rely on the settings provided by the operating system.
This example includes a box with a dashed outline set on it by default. When the prefers-contrast: more media query matches, the applied outline is given a higher contrast solid style instead.
<div class="contrast">low contrast box</div>.contrast {
margin: 5px;
width: 100px;
height: 100px;
outline: 2px dashed black;
}
@media (prefers-contrast: more) {
.contrast {
outline: 2px solid black;
}
}