.sb-board {
  display: grid;
  gap: 3px;
  margin: 8px auto;
  width: max-content;
  background: #dde4ee;
  padding: 5px;
  border-radius: 10px;
}
.sb-cell {
  width: 44px;
  height: 44px;
  border-radius: 7px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  user-select: none;
  font-size: 22px;
  transition: transform .08s;
}
.sb-cell:active { transform: scale(.93); }
.sb-cell.star { color: #f1c40f; }