.slide-board{gap:2px;padding:20px 21px 23px;max-width:480px;background:linear-gradient(125deg,#4d8ec6 0%,#236aa7 18%,#337cb7 47%,#1e5f9d 83%,#397eb5);border:1px solid #477eaa;border-radius:17px;box-shadow:inset 0 2px 3px #c4e3ffb3,inset 3px 0 4px #b1d4f459,inset -3px -4px 5px #123e7180,0 2px 1px #144875,0 5px 9px #263b4b38;position:relative}
.slide-board::before{content:'';position:absolute;inset:17px 18px 20px;border-radius:2px;box-shadow:0 0 0 1px #13416a,inset 0 2px 5px #122c4773;pointer-events:none}
.slide-board .game-cell,.slide-board .game-cell.in-place{isolation:isolate;position:relative;border:0;border-top:1px solid #fff;border-left:1px solid #fff;border-radius:2px 2px 3px 2px;background:radial-gradient(ellipse at 30% 15%,#fff 0%,#f9f9f7 48%,#f0f1ef 100%);color:#102e61;font:400 clamp(30px,6.5vw,63px) 'Times New Roman',Times,serif;box-shadow:inset -1px -1px 2px #c0c6c4,0 1px 1px #172a3c99;transition:filter .12s;overflow:visible;aspect-ratio:1}
.slide-board .game-cell::before{content:'';position:absolute;inset:0;border-radius:inherit;pointer-events:none;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence baseFrequency='.83' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Cpath fill='%23858980' opacity='.06' filter='url(%23n)' d='M0 0h140v140H0z'/%3E%3C/svg%3E")}
.slide-board .game-cell .tile-numeral{position:relative;z-index:1;display:inline-block;color:#142f62;text-shadow:0 -.5px 0 #59729a,0 .4px .3px #071b3d, .5px 1px .8px #1b2a461a;transform:translateY(-2px);letter-spacing:-2px;font-weight:400}
.slide-board .game-cell:hover:not(.blank){filter:brightness(1.025)}
.slide-board .game-cell:active:not(.blank){filter:brightness(.98)}
.slide-board .game-cell.blank{background:linear-gradient(135deg,#123a62,#1b4b76 75%,#235883);border:0;box-shadow:inset 1px 2px 5px #071a2a80;cursor:default}
.slide-board .game-cell.blank::before{display:none}
.slide-board .game-cell:focus-visible{outline:3px solid #73b9ef;outline-offset:-4px;z-index:2}