body {
  margin: 0;
  overflow:hidden;
  box-sizing: border-box;
}

.visualizer {
  width: 100%;
  display: flex;
  flex-wrap: wrap;
  background-color: #353535;
}

.renderer {
  background-color: #000;
  width: 50%;
  height: 50%;
  box-sizing:border-box;
  border: 1px solid rgba(0, 0, 0, .2);
  border-bottom: none;
  position: relative;
  overflow: hidden;
}

#r0 {
  border-top: 2px solid #03a9f4;
}

#r1 {
  border-top: 2px solid #f44336;
}

#r2 {
  border-top: 2px solid #ffeb3b;
}

#r3 {
  border-top: 2px solid #8bc34a;
}

#my-gui-container {
  position: fixed;
  top: 80px;
  right: 20px;
  z-index:1;
}