.sudoku {
	border-collapse: collapse;
	border-spacing: 0px;
	empty-cells: show;
	border: solid thick black;
}

.sudoku td {
	border: solid thin black;
	width: 1.5em;
	height: 1.5em;
	text-align: center;
}

.sudoku td input {
	border: none;
	width: 1.5em;
	height: 1.5em;
	text-align: center;
	font-size: inherit;
}

.sudoku td.t {
	border-top-width: thick;
}
.sudoku td.l {
	border-left-width: thick;
}
.sudoku td.r {
	border-right-width: thick;
}
.sudoku td.b {
	border-bottom-width: thick;
}