html,body{
    margin:0;
    padding:0;
    overflow:hidden;
    width:100vw;
    height:100vh;
    touch-action:none;
    -webkit-touch-callout:none;
    -webkit-user-select:none;
    user-select:none;
}
#game_canvas{
    cursor: none;
    display:block;
    width:100vw;
    height:100vh;
}