body {
  font-family: sans-serif;
  text-align: center;
}

#grid {
  display: grid;
  grid-template-columns: repeat(3, 80px);
  gap: 5px;
  justify-content: center;
  margin-top: 20px;
}

.cell {
  width: 80px;
  height: 80px;
  font-size: 48px;
  background: #eee;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
}