body {
    margin: 0;
    overflow: hidden;
}

#map {
    width: 100vw;
    height: 100vh;
    background-size: cover;
    transition: background 0.3s linear;
    position: relative;
}

#player {
    width: 48px;
    height: 48px;
    background: url("img/player.png");
    background-size: cover;
    position: absolute;
    top: 200px;
    left: 200px;
    transition: left 0.1s linear, top 0.1s linear;
}