body, html {
    height: 100%;
    background: #000;
}
#ball {
    width: 20px;
    height: 20px;
    background: #000;
    position:absolute;
    left: 10px;
    top: 0px;
    border: 2px solid #fff;
    border-radius: 10px;
}
.bar {
    width: 20px;
    height: 100px;
    background: #000;
    border: 2px solid #fff;
}
#bar1 {
    top: 20px;
    float: left;
    position: absolute;
}
#bar2 {
    top: 20px;
    right: 0px;
    position: absolute;
}
#line {
    width: 50%;
    border-right: #fff dashed 5px;
    height: 100%;
}



/* 24:40
https://www.youtube.com/watch?v=gRkYtMpd0AY */