.sudokuBoard {
	display: grid;
	grid-template-columns: repeat(9, 1fr);
	grid-template-rows: repeat(9, 1fr);
	gap: 1px;
	border: 1px solid #000;
	margin: 0 auto;
	width: 500px;
	height: 500px;
	background-color: darkgray;
}

.sudokuCell {
	position: relative;
	display: flex;
	justify-content: center;
	align-items: center;
	font-weight: bold;
	font-size: 24px;
	background-color: white;
}

.sudokuCellHint {
	position: absolute;
	border: 1px dashed lightgray;
	width: 30%;
	height: 30%;
	font-size: 16px;
	text-align: center;
	color: black;
}

.sudokuCellHint:nth-child(1) { left: 0; top: 0; }
.sudokuCellHint:nth-child(2) { right: 0; top: 0; }
.sudokuCellHint:nth-child(3) { left: 0; bottom: 0; }
.sudokuCellHint:nth-child(4) { right: 0; bottom: 0; }

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

.sudokuCell:nth-child(9n) {
	border-right: none;
}

.sudokuCell:nth-child(n+19):nth-child(-n+27),
.sudokuCell:nth-child(n+46):nth-child(-n+54) {
	border-bottom: 2px solid black;
}

.sudokuCell:nth-child(n+55):nth-child(-n+63) {
	border-bottom: none;
}

.sudokuCellSelected {
	background-color: yellow !important;
}

.sudokuCellSelectable {
	color: blue !important;
}

.sudokuScreenKeys {
	display: none;
	text-align: center;
	margin: 5px;
	grid-template-columns: repeat(5, 1fr);
	grid-column-gap: 5px;
	grid-row-gap: 5px;
}

.sudokuScreenKeys button {
	width: 100%;
	height: 100%;
	font-size: 28px;
	font-weight: bold;
}

.newGameDifficulty {
	display: none;
	position: absolute;
	top: 50%;
	left: 50%;
	transform: translate(-50%, -50%);
	width: 300px;
	background-color: white;
	border: 3px solid black;
	z-index: 999;
	padding: 10px;
	box-shadow: 0 0 10px 5px rgba(0, 0, 0, 0.5);
}

.sudokuPlayType {
	margin-top: 10px;
	text-align: center;
}

@media (max-width: 767px) {
	.sudokuBoard {
		width: 100%;
		height: 52vh;
	}
	.sudokuScreenKeys {
		display: grid;
	}
	.sudokuScreenKeys button {
		padding: 0;
	}
	.sudokuCell {
		font-size: 20px;
	}
}