html,
body {
    overflow: hidden;
    width: 100%;
    height: 100%;
    margin: 0;
    background-color: #09daff;
}

canvas {
    background-color: #09daff;
}

.overlay {
    position: fixed;
    display: none;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 2;
}

.overlay.tutorial {
    cursor: pointer;
    display: block;
}

.overlay-text {
    position: absolute;
    top: 50%;
    left: 50%;
    font-size: 3vmax;
    color: white;
    transform: translate(-50%, -50%);
    -ms-transform: translate(-50%, -50%);
}