body {
  font-family: Arial, sans-serif;
  text-align: center;
  padding: 20px;
  background-color: #f5f5f5;
}

#board {
  display: grid;
  grid-template-columns: repeat(5, 50px);
  grid-gap: 3px;
  justify-content: center;
  margin: 20px auto;
}

.cell {
  width: 50px;
  height: 50px;
  background-color: #ddd;
  font-size: 20px;
  font-weight: bold;
  line-height: 50px;
  cursor: pointer;
  user-select: none;
  border: 1px solid #aaa;
}

.cell.revealed {
  background-color: white;
  cursor: default;
}

.cell.bomb {
  background-color: #ff4d4d;
}