Template:Ruby/styles.css

/* {{pp-template}} */
ruby > rt,
ruby > rtc {
	font-feature-settings: 'ruby' 1;
}

ruby.large {
	font-size: 250%;
}

ruby.large > rt,
ruby.large > rtc {
	font-size: .3em;
}

This template "Ruby/styles.css" is from Wikipedia if otherwise notified