* {
  padding: 0;
  margin: 0;
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
      user-select: none;
}
.demo2-outer {
  height: 100%;
  width: 100%;
  position: absolute;
  background-color: #EEE;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
  display: -webkit-flex;
  -webkit-justify-content: center;
  -webkit-align-items: center;
}
.demo2 {
  width: 190px;
  height: 320px;
}
.demo2-ball {
  position: absolute;
  border: 1px solid black;
  border-radius: 99px;
  width: 50px;
  height: 50px;
}