.primero{
  background-color:red;
  border:10px solid blue;
  height:50px;
  width:500px;
  margin:50px;}
  .segundo{
  background-color:blue;
  border:10px solid orange;
  height:50px;
  width:500px;
  margin-left:80px;
  color:white;}
  .tercero{background-color:green;
  border:10px solid red;
  height:50px;
  width:500px;
  margin:20px 100px;
  color:white;}
  .cuarto{background-color:orange;
  border:10px solid red;
  height:50px;
  width:500px;
  text-align:center;
  margin:auto;
    float:right;}
    .div{
      background-color:black;
      color:white;
      text-align:center;
      border: 5px solid blue;
      margin: 10px 20px;
      height:200px;
      width:200px;
      float:left;}