body {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: #f0f0f0;
}



a[href="../../index.html"] {
    position: fixed;
    right: 20px;
    bottom: 20px;
    background-color: #ffffff;
    padding: 10px 20px;
    border-radius: 5px;
    text-decoration: none;
    color: #333;
    font-weight: bold;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
    transition: background-color 0.3s;
}
a[href="../../index.html"]:hover {
    background-color: #ddd;
}



#chess-board {
    display: grid;
    grid-template-columns: repeat(8, 80px);
    grid-template-rows: repeat(8, 80px);
    border: 2px solid #333;

    /* transform: rotate(180deg); */
}

.square {
    width: 80px;
    height: 80px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 2rem;
    cursor: pointer;

    /* transform: rotate(180deg); */
}

.dark {
    background-color: #769656;
}

.light {
    background-color: #eeeed2;
}


.highlight {
    background-color: rgba(0, 255, 0, 0.5); /* 半透明の緑でハイライト */
}