table {
  border-spacing: 0;
  border-collapse: collapse;
}

table > tbody { border: 2px solid black; }

table > tbody > tr > td {
  vertical-align: middle;
  text-align: center;
  width: 40px;
  height: 40px;
  border: 1px solid #adb5bd;
}

input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
    padding: 0;
}

input[type="number"] {
    -moz-appearance: textfield;
    cursor: pointer;
    text-align:center;
    margin: 0;
    padding: 0;
    border: 0px solid #ebebeb;
    color: #6c757d;
}

.sudoku-table {
  margin-left:auto;
  margin-right:auto;
}

.sudoku-block-separator-bottom {
  border-bottom:2px solid #555;
}

.sudoku-block-separator-right {
  border-right:2px solid #555;
}

.sudoku-cell {
  width: 25px;
  height: 25px;
  font-size: 14px;
  line-height: 1.42857143;
  background-color: #ffffff;
  background-image: none;
  border-radius: 0px;
}

.sudoku-not-empty-cell {
    background-color: #efefef;
    color: #000000;
    font-weight: bold;
}