body {
    background: #f0f0f0;
}

#gameArea {
    width: 400px;
    height: 400px;
    background: #fff;
    border: 2px solid #333;
    margin: 50px auto;
    position: relative;
}

#square {
    width: 40px;
    height: 40px;
    position: absolute;
    left: 0;
    top: 0;
    background-image: url('../img/character.png');
    background-size: cover;
    background-repeat: no-repeat;
}