.grid-container{display:flex;flex-direction:column;-webkit-user-select:none;user-select:none}.row{display:flex}.cell{width:40px;height:40px;border:1px solid #000;box-sizing:border-box;transition:background-color .2s}.cell.selected{background-color:#fffbe6!important}.cell-letter{color:#fff;font-size:1.3em;font-weight:700;display:flex;align-items:center;justify-content:center;height:100%;width:100%;text-align:center;pointer-events:none;-webkit-user-select:none;user-select:none}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,sans-serif;display:flex;flex-direction:column;align-items:center;min-height:100vh;margin:0;padding:20px;background:#f5f5f5}h1{text-align:center;color:#333;margin-bottom:30px}.container{background:#fff;padding:20px;border-radius:10px;box-shadow:0 2px 10px #0000001a;max-width:800px;width:100%}.game-area{display:flex;justify-content:center;gap:20px;flex-wrap:wrap}.slider-area{display:flex;flex-direction:column;align-items:center;margin-bottom:0;margin-top:30px}#grid-size-slider{width:300px;margin-bottom:8px}.slider-label{font-size:1em;color:#444;margin-top:0}.modal-overlay{position:fixed;inset:0;background:#00000059;display:flex;align-items:center;justify-content:center;z-index:1000}.modal{background:#fff;padding:32px 28px 24px;border-radius:12px;box-shadow:0 4px 32px #0000002e;min-width:280px;text-align:center}.modal-buttons{display:flex;justify-content:center;gap:18px;margin-top:18px}.modal button.confirm{background:#1976d2;color:#fff;border:none;padding:8px 22px;border-radius:5px;font-weight:500;cursor:pointer;transition:background .2s}.modal button.confirm:hover{background:#1256a3}.modal button.cancel{background:#eee;color:#333;border:none;padding:8px 22px;border-radius:5px;font-weight:500;cursor:pointer;transition:background .2s}.modal button.cancel:hover{background:#ccc}.letter-grid{display:grid;grid-template-columns:repeat(13,1fr);grid-template-rows:repeat(2,40px);gap:10px;margin-bottom:28px;justify-items:center}.letter-btn{width:36px;height:36px;border:none;border-radius:7px;color:#fff;font-size:1.1em;font-weight:700;cursor:pointer;box-shadow:0 2px 6px #00000014;transition:transform .1s,box-shadow .1s;outline:none}.letter-btn:active{transform:scale(.95);box-shadow:0 1px 2px #0000001f}.undo-btn-container{position:fixed;left:32px;bottom:32px;z-index:1100}.action-btn{width:48px;height:48px;border:none;border-radius:12px;background:#f5f5f5;box-shadow:0 2px 8px #00000014;display:flex;align-items:center;justify-content:center;cursor:pointer;transition:box-shadow .15s,background .15s;padding:0;position:relative;top:-6px}.action-btn:disabled{opacity:.4;cursor:not-allowed}.action-btn svg{display:block}.controls-bar{display:flex;align-items:center;justify-content:center;gap:1.2em;margin-top:1.5em;position:relative}.slider-area{display:flex;align-items:center;gap:1em}.congruent-modal{text-align:center}.congruent-warning-text{display:flex;align-items:center;justify-content:center;flex-wrap:wrap;gap:8px;font-size:1.15em;margin-bottom:18px}.congruent-warning-bold{font-weight:700;margin-right:6px}.congruent-rect-btn{display:inline-flex;align-items:center;justify-content:center;width:32px;height:32px;border-radius:7px;color:#fff;font-size:1.1em;font-weight:700;margin:0 6px;box-shadow:0 2px 6px #00000014;border:none}.defect-bar{display:flex;align-items:center;justify-content:center;gap:10px;font-size:1.2em;margin-bottom:10px;margin-top:8px}.defect-label{font-weight:500;color:#333}.defect-value{font-weight:700;font-size:1.2em;margin-left:6px}.defect-red{color:#d32f2f!important}.defect-green{color:#388e3c!important}.defect-separator{margin:0 10px;color:#bbb;font-weight:400}.defect-grey{color:#888}