Template:DayInMonth/style.css

@media screen {
    html.skin-theme-clientpref-night .infobox tr:not(.notheme)[style] {
	  background: transparent !important;
	}
}


@media screen and ( prefers-color-scheme: dark) {
    html.skin-theme-clientpref-os .infobox tr:not(.notheme)[style] {
		background: transparent !important;
    }
}