body {
  font-family: Arial, sans-serif;
  text-align: center;
  margin-top: 30px;
}

#grid {
  display: grid;
  grid-template-columns: repeat(5, 50px);
  grid-template-rows: repeat(5, 50px);
  gap: 5px;
  justify-content: center;
  margin: 20px auto;
}

.cell {
  width: 50px;
  height: 50px;
  border: 1px solid black;
  background: white;
  cursor: pointer;
}

.cell.active {
  background: black;
}

#result {
  margin-top: 20px;
  font-size: 24px;
}