Do the 15 days in which blood of different colors was seen during Ramadan count as a complete menstrual period, or only the first seven days, or the last seven days of them?

The maximum duration of menstruation is fifteen days. If the total number of bleeding days does not exceed fifteen days, then all of it is considered menstruation. However, if the bleeding exceeds fifteen days, then the woman is considered to be suffering from irregular bleeding (istihada), and her menstruation is then only what coincides with the time of her usual cycle.