root = Card([introText, signupForm])
introText = TextContent("Subscribe to get weekly insights and updates on our product.")
signupForm = Form("newsletter-signup", formButtons, [emailField])
emailField = FormControl("Email address", emailInput, "We only use this to reply")
emailInput = Input("email", "Enter your email", "email")
formButtons = Buttons([subscribeBtn])
subscribeBtn = Button("Subscribe", null, "primary")