First of all, I would say it is not good to use margin on the component’s top-level, because it breaks the isolation of components.// A React component with margin set on top-levelconst MyComponent = () => { return <div style="margin: 1rem">...</div>;};margin here is not just affecting the component itself, but also affecting other components (e.g., it is pushing off another component / element sitting next to it)If we want to place this component in a different context or layout, margin would get in the way of resuse