Pull quotes are a floating (or "wrapped") content type, meaning they are intended for use with the Wrapping Body Content content type. To effectively use pull quotes, they must be placed on the page immediately before a Wrapping Body Content. Starting at the same hypothetical horizontal rule across the page, the wrapping body content will fill down around an automatically padded pull quote in the position that you choose.
Like the other floating types, pull quotes are responsive. If the screen or window becomes too narrow to comfortably house the pull quote, it will automatically increase its width to 50% or 100% of the page width in order to make enough room, and will re-flow or push down its companion Wrapping Body Content.