RFC (https://tools.ietf.org) dark mode. Use https://addons.mozilla.org/pt-BR/firefox/addon/codeinjector and add this rule.

README.md

before	after

rfc-darkmode.css

/* dark mode RFC by @micalevisk */

body {
    background: #010409;
    color: #c9d1d9;
}

span.docinfo {
	background-color: rgba(240,246,252,0.15) !important;
}

a:link {
    color: #58a6ff;
    background-color: transparent;
    text-decoration: none;
}
a:visited {
    color: pink;
    background-color: transparent;
    text-decoration: none;
}
a:hover {
    color: rgba(152, 206, 255, 0.51);
    background-color: transparent;
    text-decoration: underline;
}
a:active {
    color: yellow;
    background-color: transparent;
    text-decoration: underline;
}