h1 {
  text-align: center;
}

#board-container {
  margin-top: 64px;
  text-align: center;
}

.row {
  display: flex;
  justify-content: center;
}

.cell {
  width: 50px;
  height: 50px;
  border: 1px solid black;
  box-sizing: border-box;
}