*{margin:0;padding:0;box-sizing:border-box;user-select:none;font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Oxygen,Ubuntu,Cantarell,"Open Sans","Helvetica Neue",sans-serif}.container{height:100svh;display:grid;place-items:center;padding:1rem;background-color:#f4f4f4}.grid{display:grid;aspect-ratio:1/1;width:min(88vw,70svh,560px);padding:.75rem;border-radius:14px;background-color:#222;box-shadow:0 16px 32px rgba(0,0,0,.2);grid-template:1fr 1fr 1fr/1fr 1fr 1fr;gap:.5rem}.grid .cell{border:0;border-radius:8px;background-color:#fff;aspect-ratio:1/1;font-size:clamp(3rem,18vw,8rem);display:grid;place-items:center;color:#222;cursor:pointer;transition:background-color .2s,transform .2s}.grid .cell:hover{background-color:#e8e8e8;transform:translateY(-2px)}dialog{position:absolute;left:50%;top:5%;transform:translate(-50%);width:min(90vw,420px);border:0;border-radius:10px;padding:1rem;text-align:center;font-size:clamp(2rem,12vw,4rem);background-color:#222;color:#fff;box-shadow:0 12px 24px rgba(0,0,0,.2)}dialog:focus{outline:none}