#tictactoe-board {
    display: grid;
    grid-template-columns: repeat(3, 60px);
    grid-template-rows: repeat(3, 60px);
    gap: 5px;
    margin: 20px 0;
}
.ttt-cell {
    background: #fff;
    border: 2px var(--cyan) solid;
    font-size: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    height: 60px;
    width: 60px;
    user-select: none;
    transition: background 0.2s;
}
.ttt-cell:hover {
    background: var(--pink);
}