p {
  margin: 0.5rem;
  text-align: center;
}
p:first-child {
  margin-top: 15px;
}

#resume {
  display: none;
}

.time {
  font-weight: 20px;
}
.time .minutes, .time .seconds {
  margin: 0 -2px;
}
.time .colon {
  position: relative;
  bottom: 1px;
  margin: 0 -2px;
}

.adjust {
  width: 400px;
  margin: auto;
  text-align: center;
}
.adjust .difficulty {
  width: 150px;
}

.immutable {
  font-weight: bold;
}

.numbers-bar {
  width: 475px;
  margin: 5px auto;
  box-sizing: border-box;
}
.numbers-bar .number {
  background-color: #ffddbb;
  float: left;
  border: 1px solid #000;
  height: 50px;
  width: 50px;
  box-sizing: content-box;
  font-size: 30px;
  text-align: center;
}
.numbers-bar .number:nth-child(3), .numbers-bar .number:nth-child(6) {
  margin-right: 3px;
}
.numbers-bar .number:hover {
  background-color: #BBDDFF;
}

.sudoku {
  width: 475px;
  margin: auto;
}
.sudoku .square {
  float: left;
  border: 1px solid #000;
}
.sudoku .square .cell {
  float: left;
  position: relative;
  height: 50px;
  width: 50px;
  background: #fff;
  border: 1px solid #000;
  box-sizing: content-box;
}
.sudoku .square .cell:hover {
  background-color: #BBDDFF;
}
.sudoku .square .cell:hover .label {
  color: #333;
}
.sudoku .square .cell.selected {
  background-color: #76A8FF;
}
.sudoku .square .cell.selected .label {
  color: #333;
}
.sudoku .square .cell.error {
  background-color: #E58080;
}
.sudoku .square .cell.valid {
  background-color: #95E595;
}
.sudoku .square .cell .label {
  position: absolute;
  color: #aaa;
  top: 1px;
  left: 2px;
  font-size: 12px;
}
.sudoku .square .cell .value {
  display: block;
  font-size: 30px;
  color: #000;
  width: 100%;
  height: 100%;
  text-align: center;
}
.sudoku .square .cell:nth-child(3n+1) {
  clear: both;
}

#congratsModal {
  display: none;
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  background: rgba(0,0,0,0.5);
  z-index: 9999;
  justify-content: center;
  align-items: center;
  display: flex;
}
#congratsModal > div {
  background: #fff;
  padding: 32px 48px;
  border-radius: 12px;
  box-shadow: 0 2px 16px rgba(0,0,0,0.2);
  text-align: center;
  max-width: 90vw;
}