root = Card([header, question, poll, voteActions])
header = CardHeader("Team Lunch", "Weekly team poll")
question = TextContent("Where should we go for lunch on Friday?", "large")
poll = RadioGroup("lunch_choice", [sushiItem, tacosItem, pizzaItem])
sushiItem = RadioItem("Sushi Place", "Fresh rolls and sashimi", "sushi")
tacosItem = RadioItem("Taco Stand", "Street tacos and burritos", "tacos")
pizzaItem = RadioItem("Pizza Joint", "Wood-fired slices", "pizza")
voteActions = Buttons([voteBtn])
voteBtn = Button("Vote", null, "primary")