I'm not sure this is a great idea, but I'll at least present the idea. At Brigade, we have a button component with some box shadow. When it is rendered on top of the page, some of the box shadow is rendered off-screen. Because of that, we wrap our happo rendering of buttons in a div with some padding. If the document that we render examples in had some built-in padding, we wouldn't have a need for the wrapper.
This is probably a bad idea after all. It's likely that happo examples rely on a going full-width (think responsive full-width components rendered on small screens).
I'm not sure this is a great idea, but I'll at least present the idea. At Brigade, we have a button component with some box shadow. When it is rendered on top of the page, some of the box shadow is rendered off-screen. Because of that, we wrap our happo rendering of buttons in a div with some padding. If the document that we render examples in had some built-in padding, we wouldn't have a need for the wrapper.