css javascript black and white mode code example

Example 1: css image filter black and white

-webkit-filter: grayscale(100%); /* Safari 6.0 - 9.0 */
  filter: grayscale(100%);

Example 2: css dark mode

@media (prefers-color-scheme: dark) {
  body {
    background-color: black;
    color: white;
  }
}