.caja {
	width: 100%;
	margin-left: auto;
	margin-right: auto;
	font-family: "MS Serif", "New York", serif;
}
.caja header {
	color: white;
	shape-outside: border-box;

	transition-property: color;
	transition-duration: 1s;
	transition-delay: .2s;
	transition-timing-function: linear;
	width:100%;
	text-align:center;
	margin-bottom:0.2em;
}
h1 {
	font-size: 100;
	background-color:green; 
	opacity: 0.7;
	transition-property: color;
	transition-duration: 1s;
	transition-delay: .2s;
	transition-timing-function: linear; 
	margin:0;
}
.contenido {
	margin-bottom:0.2em;
	display:flex;
	flex-direction: row;
}
article {
	background-color: lightblue; 
	opacity: 0.88;
	flex-basis: 70%;
	margin-right:0.2em;

}
aside {
	background-color: lightgray;
	opacity: 0.9;
	flex-basis: 30%;
	margin-left: 0.2em;
	text-align: center;
	font-family: "Times New Roman", Times, serif;

}
footer {
	background-color:green;
	opacity: 0.7;
	color: white;
}
.caja header h1 strong {
	font-family: "Comic Sans MS", cursive;
	font-size: 36px;
}
.f {
	font-family: Georgia, "Times New Roman", Times, serif;
}