body {
    background-color: #000000;
    margin: 0px;
    overflow: hidden;
}

#container {
    width: 100%;
    height: 100vh;
    position: relative;
}

canvas, #overlay {
    width: 100%;
    height: 100%;
    position: absolute;
    left: 0;
    top: 0;
}

#overlay {
    background: url('trees.png') center;
    background-size: cover;
    z-index: 1000;
}