[SOLVED] Notification icon styling ignored

With this code I get the correct icon and message text but the icon styling (colour and size) is ignored - have I done something wrong?

	var notificationFull = app.notification.create({
	  icon: '<i class="f7-icons color-red ">close_round_fill</i>', 
	  title: 'Answer Error',
	  titleRightText: '',
	  subtitle: 'Incorrect entry',
	  text: 'Answer must be numeric digits only',
	  closeTimeout: 3000,

not clear that sterol attributes need to be added to a local css file; this solve the colour problem:

.color-red {
color: red;