The rules of "Red" are simple: highest card wins! But "Red" is just one of seven games you'll be playing in Red7, and if you're not winning the current game at the end of your turn, you're out! The last person standing wins the round.
The deck is 49 cards, numbered 1-7 in each of the seven rainbow colors. A 7 is always higher than a 6, but for cards of the same number, a Red is the highest and Violet the lowest.