root = Card([header, uptimeSection, incidentCallout])
header = CardHeader("Platform Status", "API health this month")
uptimeSection = Card([uptimeLabel, uptimeValue])
uptimeLabel = TextContent("Uptime this month", "default")
uptimeValue = TextContent("99.9%", "large")
incidentCallout = Callout("warning", "Recent Incident", "Service degradation observed on 2025-09-18, resolved by 2025-09-19 14:30 UTC")