cs_* {
margin: 100px;
padding: 100px;
}




<script> 

var ventana_secundaria 

function abrirVentana(){ 

ventana_secundaria = window.open("quiensoy2.html","miventana","width=300,height=200,menubar=no") 
} 

function cerrarVentana(){ 
 
ventana_secundaria.close() 
} 
</script> 



		<title>Menu Desplegable</title>
		<style type="text/css">
			
			* {
				margin:0px;
				padding:0px;
			}
			
			#header {
				 margin:0 auto; /* Centramos automaticamente*/
				width:1300px; /*Le establecemos un ancho*/
				font-family:Arial, Helvetica, sans-serif;
				font-size: 25px;  /*Tamaño de la fuente*/
			}
			
			ul, ol {
				list-style:none;
			}
			
			.nav > li {
				float:left;
			}
			
			.nav li a {
				background-color:#000;
				color:#fff;
				text-decoration:none;
				padding:40px 12px;
				display:block;
			}
			
			.nav li a:hover {
				background-color:#434343;
			}
			
			.nav li ul {
				display:none;
				position:absolute;
				min-width:140px;
			}
			
			.nav li:hover > ul {
				display:block;
			}
			
			.nav li ul li {
				position:relative;
			}
			
			.nav li ul li ul {
				right:-140px;
				top:0px;
			}
			
		</style>
#cabecera {
	background: #FFFBB9;
	border: 1px solid #999999;
	padding: 20px;
	}
cs_t1 { 
font:  italic normal 100 40px verdana ; Arial; color: blue;  background: red;
 }
cs_h1 {
font:  normal small-caps bold 24px verdana, Courier; color: green;  background:#CCCCCC; 
}
cs_h2 {
font: oblique normal 550  18px verdana, sans-serif;  color: yellow;
}
cs_h3 {
font:  normal small-caps bold 17px verdana, sans-serif;  color: green; 
}





header, section, footer, aside, nav, article, figure, figcaption,
hgroup{
display: block;
}

body {
text-align: center;
}


#agrupar {
width: 960px;
margin: 15px auto;
text-align: left;
}