How ENUM memory allocation works?

Today I was playing with Enum then I realized something is wrong it's mem allocation or maybe I am wrong but please tell me how an enum is able to store a 4bytes of int into a 1byte mem when I explicitly declared the type to char.

enum suit : char  {club = 20,diamonds = 10,hearts = 20} card;

//driver fn

int main()
{
   
    card = club;
    cout << "Size of enum variable " << sizeof(card) << " "<<sizeof(club) <<" bytes."<<"\n";  
       return 0;
}

//output

Size of enum variable 1 1 bytes.