.board-square {
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    position: relative;
}

.square-light {
    background: #f0d9b5;
}

.square-dark {
    background: #b58863;
}

.piece {
    width: 85%;
    height: 85%;
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
}

.selected {
    outline: 3px solid yellow;
}