h1 {
  font-size: 50px;
  text-align: center;
  background-color: pink;
  color: blue;
  border: 5px solid blue;
  border: 3px solid red;
}

h2 {
  font-size: 30px;
  background-color: blue;
  color: pink;
  border: 5px solid pink;
}
body{
  background-color: dimgrey;
  font-size: 20px;
  text-align: center;

}
canvas {

margin-left: auto;

margin-right: auto;

display: block;

}
.caja {
  width: 300px;
  height: 120px; 
  background: linear-gradient(90deg, red, yellow, red);
  border: 2px solid black;
  align-content: center;
  text-align: center;
  margin: 0 auto;
  font-weight: bold;
}
.caja1
{
  width: 300px;
  height: 120px; 
  background: whitesmoke;
  border: 2px solid black;
  align-content: center;
  text-align: center;
  margin: 0 auto;
  font-weight: bold;
}