An example state machine that also maintains css state.

machina.css-state.js

var Lightswitch = machina.Fsm.extend({

	initialState: "off",

	states: {
		off: {

		},
		on: {

		}
	}
});


var LightswitchView = Backbone.View.extend({
	initialize: function () {
		this.fsm = new Lightswitch();

		var self = this;
		this.fsm.on( "transition", function ( data ){
			if ( data.fromState ) {
				self.$el.removeClass( "is-" + data.fromState );
			}

			if ( data.toState ) {
				self.$el.addClass( "is-" + data.toState );
			}
		});
	}
});