body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 20px;
}

h1 {
    text-align: center;
}

#board {
    display: grid;
    grid-template-columns: repeat(19, 30px);
    grid-gap: 1px;
}

.square {
    width: 30px;
    height: 30px;
    background-color: #f0f0f0;
    border: 1px solid #ddd;
    cursor: pointer;
}

.square.black {
    background-color: black;
}

.square.white {
    background-color: white;
}

#history {
    max-width: 200px;
    color: #444;
}

#history ul {
    padding-left: 0;
}

#history li {
    list-style: none;
}