* {
  margin: 0;
  padding: 0;
}
section {
  width: 90%;
  display: block;
  margin: 0 auto;
}
article {
  border: 1px solid #000;
  text-align: center;
}
article h1 {
  padding: 10px 20px;
  margin: 10px 0;
  font-family: 'Roboto', sans-serif;
  font-size: 1.5em;
  text-align: left;
}
article#imagen h1 {
  background-color: #454545;
  color: #AAA9A9;
}
article#video h1 {
  background-color: #575757;
  color: #B8B6B6;
}
article#vectorial h1 {
  background-color: #686868;
  color: #C6C5C5;
}