Are hymen, which are pink in colour, means that they are thick? and what is the function/purpose of hymen? plz ans both of my questions

No & it's a remnant: The hymen will be pink regardless of how thick it is. In a developing fetus, the vagina grows down from the top and up from the bottom and the hymen is where the two parts meet, like two halves of a tunnel meeting in the middle. The point where they meet has to break down for there to be a complete vagina, and sometimes this process is incomplete, leaving a thicker and more complete hymen.