body{
  background-color: lightblue;
  padding: 20px;
  font-style: helvetica;
}
header{
  background-color: lightgrey;
}
img{
  height:300px;
  width: 500px;
  margin:0 auto;
  padding:10px;
}
.demolicion
{
  height: 200px;
  width: 400px;
}