#new-game {
    position: relative;
}

#new-game input[type="submit"] {
    position: absolute;
    top: 0;
    height: 3.5em;
    width: 8em;
}

/* game board table */

.board td {
    width: 50px;
    height: 50px;
    border: solid 1px #666;
}

/* pieces are div within game table cells: draw as colored circles */

.piece {
    margin: 5px;
    width: 80%;
    height: 80%;
    border-radius: 50%;

    background-color: var(--color);
}

/* column-top is table row of clickable areas for each column */

.column-top td {
    border: dashed 1px lightgray;
}

.column-top td:hover {
    background-color: gold;
}