*{
    padding: 0;
    margin: 0;
    box-sizing: border-box;

}
body{
    font-family: Arial, Helvetica, sans-serif;
    font-size: 30px;
    font-weight: 700;
    color: black;
}

h2{
    text-align: center;
    margin: 20px ;
}

table{
    margin: 0 auto;
    border-collapse: collapse;
}

td {
  width: 80px;
  height: 80px;
  border: 1px solid black;
}

.square_black {
  background-color: #333;
}

.square_white {
  background-color: #fff;
}