/* On screens that are 992px or less, set the background color to blue */
@media screen and (max-width: 992px) {
  .propo {
    width:600px;
  }
}

/* On screens that are 600px or less, set the background color to olive */
@media screen and (max-width: 600px) {
  .propo {
    width:500px;
  }
}

/* On screens that are 600px or less, set the background color to olive */
@media screen and (max-width: 578px) {
  .propo {
    width:300px;
	height:150px;
  }
}