The provided evidence confirms the Forbidden City's colors (red and yellow) and its general history, but does not mention specific rules regarding the number or color of golden door nails.

The evidence provided describes the Forbidden City's general history and location but contains no mention of a ritual belief regarding women touching the entrance to be granted a son.

The evidence provided is irrelevant; one source is about a video game (Sons of the Forest) and another is a social media video. No authoritative source confirms that golden door nails were exclusive to the royal family.

While the evidence confirms the dates of the Ming and Qing dynasties and that dragons were symbols of hierarchy, there is no mention of 'door nails' specifically serving as symbols of hierarchy or being bound by strict rules.

One web search result ('The Doors of Opportunity Exploring China's Thriving Door Culture') mentions that odd numbers of panels are preferred because they reconcile yin and yang. However, this refers to panels, not specifically 'door nails', and there is only one source providing this conceptual link.

One source ('Why Number Nine Prevails in the Forbidden City?') confirms that nine is seen as a powerful number with masculine energy and a connection to divine power in Chinese philosophy. However, it does not explicitly link this to the specific count of 'door nails' as an exclusive imperial symbol in the provided text.