LayoutTests/resources/testharness.css

html {
    font-family:DejaVu Sans, Bitstream Vera Sans, Arial, Sans;
}

table#results {
    border-collapse:collapse;
}

table#results th {
    padding:0;
    padding-bottom:0.5em;
    border-bottom:medium solid black;
}

table#results td {
    padding:0;
    padding-bottom:0.5em;
    border-bottom:thin solid black;
}

table#results tr>td:nth-child(1) {
    font-variant:small-caps;
}

table#results tr>td:nth-child(3) {
    font-family:DejaVu Sans Mono, Bitstream Vera Sans Mono, Monospace;
    white-space:pre;
}