2 different rules for minimum quantity on 1 product

Hi guys! I hope you’d be able to help me, as 2 days of web search delivered no results.

I am trying to set up 2 different rules on a product, so that the customer is required to purchase a minimum qty PER SIZE, but there is also a minimum order qty on the product itself (for example: minimum 20 per size, minimum 120 in total;)

Any push in a good direction is much appreciated!

O