@media (prefers-color-scheme: dark) {
    html body {filter: invert(1);}
    /* the following really should be managed by a cascade layer */
    .some-container-items-or-images {
      box-shadow: 0.25em 0.25em 0.67em #FFF8;
    }
}

From Lary Hudson

you should also set “color-scheme: dark” so that scrollbars change to a dark tint as well.

A search engine for books.

EDIT 2023-08-25: it stores their books now, and it is the biggest library of the world!