nextcloud/core/css/fonts.css

@font-face {
	font-family: 'OpenSans';
	font-weight: normal;
	src: url(../fonts/OpenSans-Regular.ttf);
}

@font-face {
	font-family: 'OpenSans';
	font-weight: bold;
	src: url(../fonts/OpenSans-Bold.ttf);
}