.one,
.two,
.three {
  height: 700px;
  line-height: 700px;
  font-size: 30px;
  text-align: center;
}

.one {
  background: greenyellow;
}

.two {
  background: red;
}

.three {
  background: #ddd;
}

.popover{
  position: fixed;
  left: 220px;
  top:120px;
  z-index: 10;
}