body {
  height: 100vh;
  margin: 0;
}

.EmbedTest {

  position: absolute;
  top: 100px;
  left: 100px;
  width: 400px;
  height: 400px;
  background-color: red;
}

.EmbedTest2 {

  position: absolute;
  top: 200px;
  left: 600px;
  width: 500px;
  height: 500px;
}

.EmbedTest3 {

  position: absolute;
  top: 600px;
  left: 300px;
  width: 200px;
  height: 200px;
  background-color: black;
}