html, body, div, span, applet, object, iframe,h1, h2, h3, h4, h5, h6, p, blockquote, pre,a, abbr, acronym, address, big, cite, code,del, dfn, em, img, ins, kbd, q, s, samp,small, strike, strong, sub, sup, tt, var,
b, u, i, center,dl, dt, dd, ol, ul, li,fieldset, form, label, legend,table, caption, tbody, tfoot, thead, tr, th, td,article, aside, canvas, details, embed, 
figure, figcaption, footer, header, hgroup, menu, nav, output, ruby, section, summary,time, mark, audio, video {
	margin: 0;
	padding: 0;
	border: 0;
	font-size: 100%;
	font: inherit;
	vertical-align: baseline;
}
/* HTML5 display-role reset for older browsers */
article, aside, details, figcaption, figure, footer, header, hgroup, menu, nav, section {display: block;}
body {line-height: 1;}
ol, ul {list-style: none;}
blockquote, q {quotes: none;}
blockquote:before, blockquote:after,
q:before, q:after {
	content: '';
	content: none;
}
table {
	border-collapse: collapse;
	border-spacing: 0;
}
.contenido-block {max-width:600px; margin:0px;}
.contenido-block .imagen{margin:0px; text-align:center; display:block;}
.contenido-block img {width:100%}
.contenido-block .imagen2{display: none;}

@media only screen and (max-width: 580px) {
	.contenido-block .imagen{display: none;}
	.contenido-block .imagen2{display:block; margin:0px; text-align:center;}
}