body 		{ background: #888;font-size: large; }
nav       { float: left; width: 15%; height: 400px ;}
nav ul li { display: block;}
section   { float: right; width: 80%; height: 400px;}
iframe#galeria {height: 350px; padding: 0px;}
footer    { clear: both;  display: block; }
img#retrato			 { width: 60px;}
#contenedor:after { content: "Aspecto para tablet"; }