The CSS used (as of December 2020) is (or is based on) http://digitus.itk.ppke.hu/~cstamas/local.css. In case this page disappears, it is copy/pasted below.

/* This template is based on:
 * "Embedded Moose local.css for use with ikiwiki
 * Written by Josh Triplett <josh@freedesktop.org>
 * Some ideas from the Debian lighttpd index.html page."
 * 
 * The improved version is made by
 * Csillag Tamas <cstamas@digitus.itk.ppke.hu>
 * 2008-01-??
 * */

body { 
           background: #474747;
}

.blogform {
           background: #474747;
       color: #acacac !important;
}


.sidebar {
       background: #333333;
       color: #acacac !important;
}

.month-calendar-day-this-day {
           color: black;
           background: yellow;
}

.month-calendar-day-this-day a {
           color: white;
           background: #333333;
}

#content, .comment {
           background: #333333;
           margin: 10px 0px;
       border: 1px dotted #c0c0c0;
       padding: 10px;
       font-family: sans-serif;
       color: #acacac
}

h1 {
           font-size: 150%;
           color: #e6deee;
}

h2 {
           font-size: 130%;
           color: #e6deee;
}

a {
       color: #efefef;
       border-bottom: 1px dashed;
       text-decoration: none;
}

a:hover {
       color: black !important;
           background: yellow;
}

pre {
           color: #d0d0d0;
       border: 1px dotted #c0c0c0;
           background: black;
           padding: 2px;
           font-size: 110%;
}

.feedbutton { background: #ff0000; }

.header, .comment-header {
           background: #800000;
       border: 2px solid #500000;
       padding: 4px;
       color: #efefef;
       font-family: sans-serif;
}

.header a { margin-right: 1ex; color: #efefef; font-family: sans-serif;}
.pagedate, .tags, #backlinks { background: #640000; border: 2px solid #500000; padding: 4px; color: #efefef; font-family: sans-serif;}
.tags { color: yellow }
.selflink { background: yellow; color: black }

.actions ul {
           background: #640000;
           border: none;
           padding-bottom: 0px;
           height: 1.4em;
           font-family: sans-serif;
}

.actions a  { margin-right: 1ex; color: #dfdfdf; font-family: sans-serif;}
#footer { border: none; font-family: sans-serif;}