nextcloud/core/css/fonts.css

@font-face {
	font-family: 'Open Sans';
	font-style: normal;
	font-weight: normal;
	src: local('Open Sans'), local('OpenSans'), url(../fonts/OpenSans-Regular.woff) format('woff');
}

@font-face {
	font-family: 'Open Sans';
	font-style: normal;
	font-weight: bold;
	src: local('Open Sans Bold'), local('OpenSans-Bold'), url(../fonts/OpenSans-Bold.woff) format('woff');
}