* {
  margin: 0px;
  padding: 0px;
}
h1 {
  font: bold 20px verdana, sans-serif; 
}
h2 {
  font: bold 14px verdana, sans-serif;
}
header, section, footer, aside, nav, article, figure, figcaption, hgroup {
  display: block; 
}
body {
  text-align: center; 
  font: 1em verdana, sans-serif;
}

#caja_principal { 
  width: 90%; 
  margin: 15px auto; 
  text-align: left;
}

#cabecera {
 
 
  padding: 20px;
  text-align: center;
}

#area_principal { 
  float: left; 
  width: 71%; 
  margin: 2em 1em; 
} 

#barra_lateral {
  float: left; 
  width: 22%; 
  margin: 2em 1em; 
  padding: 0.5em;
  background: #CCCCCC;
  border: 1px solid #999999; 
}

#barra_lateral article{
  margin: 1em 0em; 
  padding: 0.5em;
  width: 92%
}

#pie {
  clear: both;
  text-align: center;
  padding: 20px;
  border-top: 2px solid #999999;
  font-size: 0.7em;
}

#pieinter {
  clear: both;
    background: #CCCCCC;
  
  text-align: center;
  padding: 20px;
  border-top: 1px solid #999999;
  border-bottom: 1px solid #999999;
}


article {
  background: #FFFBCC; 
  border: 1px solid #999999; 
  padding: 0.5em; 
  margin-bottom: 1em;
  height: auto;
  width: 100%
}
article footer {
  text-align: right; 
}
#area_principal article img{
   margin: 0.4em;
}

div {
  width: 100px;
  margin: 20px;
  padding: 10px;
  border: 0px solid #000000;
  -moz-box-sizing: border-box; 
  -webkit-box-sizing: border-box; 
  box-sizing: border-box;
}
.imagedes{
     border: 1pt #909db3 solid;
     border-radius: 5px;
     box-shadow: rgb(150,150,150) 2px 2px 5px;
     margin: 0px 10px;
}