style.css

body {
    background-color: black;
}

/* Lots of CSS to get the game to position gracefully in the center of the viewport */

#game {
    min-height: 550px;
    min-width: 450px;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

@media (max-height: 550px) {
    #game {
        position: absolute;
        top: 0%;
        transform: translateX(-50%);
    };
}

@media (max-width: 450px) {
    #game {
        position: absolute;
        left: 0%;
        transform: translateY(-50%);
    };
}

@media (max-height: 550px) and (max-width: 450px) {
    #game {
        position: absolute;
        top: 0%;
        left 0%;
        transform: translate(0%, 0%);
    };
}

#board {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: max-content;
}

/* game board table CSS */

#board td {
    width: 50px;
    height: 50px;
    border: solid 1px white;
    position: relative;
}
  
/* pieces are div within game table cells: they draw as colored circles */
  
.piece {
    border-radius: 50%;
    margin: 5px;
    width: 80%;
    height: 80%;
    position: absolute;
    top: 0px;
    left: 0px;
}

/* piece animation CSS - additional CSS for the animations is generated via JS at runtime */

.piece:not(.top) {
    animation-timing-function: ease-in;
}

.p1 {
    background-color: cyan;
}

.p2 {
    background-color: magenta;
}

/* Game title CSS - this code (along with some JS) makes the title display in the current player's color. */

h1 {
    color: white;
    text-align: center;
}

h1.p1 {
    background-color: black;
    color: cyan;
}

h1.p2 {
    background-color: black;
    color: magenta;
}

/* Top Row CSS - this code styles the divs in the top row for the move indicator */

.top {
    background-color: black;
}

.top.p1:hover {
    background-color: cyan;
}

.top.p2:hover {
    background-color: magenta;
}

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

#column-top td {
    border: dashed 1px white;
}