html {background-color:steelblue;}

#stage {
  border: 1em solid;
  border-color: #D2AB6F #8C6529;
}

#felt {
  position: relative;
  margin: 0 0 0 200px;
  height: 500px;
  background: green;
  background-image: repeating-linear-gradient(to top left, rgba(255,255,255,0), rgba(255,255,255,0) 80px, rgba(255,255,255,0.2) 80px, rgba(255,255,255,0.2) 150px);
  box-shadow: inset 0 0 10px rgba(0,0,0,0.4);
}

#felt div {
  position: absolute;
  left: -140px;
  top: 100px;
  z-index: 0;
  transition-property: left, top, -webkit-transform;
  transition-timing-function: ease-out, ease-out, ease-in-out;
  transition-duration: 0.5s;
}
#felt div:nth-child(odd) {
  margin-top: 1px;
  margin-left: 2px;
  transform: rotate(1deg);
}
#felt div:nth-child(3n) {
  margin-top: -2px;
  margin-left: -1px;
  transform: rotate(-1deg);
}