body {
  background-color: black;
  color: white;
  font-family: Arial, sans-serif;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.board {
  display: grid;
  grid-template-columns: repeat(9, 40px);
  grid-template-rows: repeat(9, 40px);
  gap: 1px;
  background-color: black;
  padding: 10px;
  margin-bottom: 20px;
}

.cell {
  width: 40px;
  height: 40px;
  background-color: white;
  text-align: center;
  color: black;
  font-size: 24px;
  font-weight: bold;
  border: 1px solid black;
}

.cell:nth-child(3n),
.cell:nth-child(6n) {
  border-right: 2px solid black;
}

.cell:nth-child(27n),
.cell:nth-child(54n) {
  border-bottom: 2px solid black;
}

.controls {
  display: flex;
  gap: 10px;
  margin-bottom: 20px;
}

a {
  color: #8cc4d1;
  text-decoration: none;
}

a:visited {
  color: #a0a0a0;
}

a:hover {
  color: orange;
  text-decoration: underline;
}