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                <h2>Background-size: contain</h2>
<p>La imagen de fondo se muestra en su tamaño real, sin importar si deja espacios sin cubrir del contenedor.</p>
<div class="contain">

<h2>Background-size: cover</h2>
<p>La imagen de fondo se acomoda en todo el espacio del contenedor, lo cual podría estirar o recortar un poco la imagen.</p>

<div class="cover">



                div {
  background-image: url('');
  background-repeat: no-repeat;
  width: 600px;
  height: 500px;
  border: 1px solid black;

  background-size: contain;

  background-size: cover;

/* Lo siguiente es CSS extra por aspectos visuales.*/
h2, p{
  font-family: sans-serif;
  margin-bottom: 0px;
  margin-top: 0px;