.Grid{display:grid;grid-template-rows:repeat(4,1fr);grid-template-columns:repeat(4,1fr);width:min(80vw,400px);aspect-ratio:1;margin:2rem auto;--tileSize: 2}.Cell{width:100%;height:100%;background:#f0f0f0;border:1px solid #bbb;font-size:1.5rem;font-family:monospace;-webkit-user-select:none;user-select:none;color:#222;box-sizing:border-box;text-align:center;transition:background-color .2s ease-in-out}.Cell[type=number]::-webkit-inner-spin-button,.Cell[type=number]::-webkit-outer-spin-button{-webkit-appearance:none;margin:0}.Cell[type=number]{-moz-appearance:textfield}.Cell:hover{background:#ccc}.Cell--visible{color:#00f}.Cell--incorrect{color:red;background:#f006}.Cell--topEdge{border-top:2.5px solid #000}.Cell--leftEdge{border-left:2.5px solid #000}.Cell--bottomEdge{border-bottom:2.5px solid #000}.Cell--rightEdge{border-right:2.5px solid #000}.Cell--highlight-row,.Cell--highlight-col,.Cell--highlight-tile{background:#e0f4ff}.Cell:focus{background:#b3e0ff!important;outline:2px solid #3399ff;z-index:1;position:relative}