body {
   position: absolute;
   top: 0;
   bottom: 0;
   left: 0;
   right: 0;
}

.sample-tutorial {
   position: relative;
   height: 100%;
   overflow: hidden;
}

#demo-host {
    width: 100%;
    height: 100%;
    overflow: hidden;
    float: left;
 }

#spread-host {
    position: absolute;
    top: 0;
    left: 0;
    width: calc(100% - 380px);
    height: 100%;
}

#panel-host {
    position: absolute;
    top: 0;
    right: 0;
    width: 380px;
    height: 100%;
}