Well don't know about that blue n pink collar stuff. (May be blue collar can be termed Mazdoor tabqa in urdu)

But there is difference between White collar nd Safaid posh.

Safaid posh is more "A honest person having low level of income but fulfilling his basic needs without asking help from others" as mentioned by Mr Sociologist

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You were not born a winner, and you were not born a loser. You are what you make yourself be.