What is square seven?

Box 7 is in poker. The following is a brief introduction to poker:

Poker (English: Poker) has two meanings, one refers to playing cards, and the other refers to games played with cards, which are called poker games, such as old K Texas Hold 'em. Author Fan published the novel Poker of the same name.

Poker has 54 cards and belongs to the category of 14. There are four cards in each category except King and King. These four cards are divided into four patterns, one of which is called a square. If there is a 7, its pattern is square, which is called "Fang Qi" for short.

In addition, there is other meaning in Box 7: Spring, summer, autumn and winter are represented by peaches, hearts, plums and diamonds respectively, in which spades and clubs represent night, hearts and diamonds represent day, and diamonds and wealth. Four colors are people's good wishes for the year.