.sideB {
    overflow:hidden;
    width: 300px !important;
    height: 600px !important;

}
.sideB iframe {
    overflow: hidden;
    position: absolute;
    top:0;
    left:0;
    display: block;
    width: 100%;
    height: 100%;
}
.game header, #game header {
  z-index: 5
}