html {
  font-size: 0.9em !important;
  line-height: 1.3 !important;
  text-align: justify;
  font-family: Verdana, Helvetica, sans-serif;
}

body {
  margin: 0;
  background: #f3f3f3;
}

blockquote {
  font-size: 1.2em;
  line-height: 2;
  margin: 1em 0 1em 3em;
  padding-left: 1em;
  border-left: 0.5em solid #336699;
}


.encabezado {
  text-align: center;
  background: #006699;
  border-bottom: 0.1em solid silver;  
  padding: 0.5em;
  }


.footer-principal {
  text-align: center;
  background: #006699;
  border-bottom: 0.1em solid silver;  
  padding: 1em;
  }

.principal {
  max-width: 900px;
  margin: auto;
  padding: 1em;
}

.caja1 {
  background: #fff;
  border: 0.1em solid gray;
  padding: 1em;
  margin: 1em;
  box-shadow: 0 0 0.1em 0.01em black;
}

.caja1 h1 {
  font-family: 'Verdana', sans-serif;
  font-size: 1.6em;
  color: darkblue;
  text-shadow: 0.03em 0.03em 0.01em #000;
  letter-spacing: 0.03em;
}

.caja1 h2 {
  font-family: 'Verdana', sans-serif;
  color: darkblue;
  text-shadow: 0.03em 0.03em 0.01em #000;
  letter-spacing: 0.03em;
}

.caja2 {
  background: #fff;
  border: 0.1em solid gray;
  padding: 1em;
  margin: 1em;
  box-shadow: 0 0 0.1em 0.01em black;
}

.caja2 h2 {
  font-family: 'Verdana', sans-serif;
  color: darkblue;
  text-shadow: 0.03em 0.03em 0.01em #000;
  letter-spacing: 0.03em;
}

.articulo {
  margin-top: 2em;
}

.solucion li {
  font-family: Arial, Helvetica, sans-serif;
  font-size: 0.9em;
  color: #331f16;
}

.solucion h1 { 
  margin: 0em;
  padding: 0em;
  text-transform: none;
  font-family: 'Verdana', sans-serif;
  font-size: 1.3em;
  color: #887644;
}

.solucion h2 { font-size: 1.2em; }

.solucion h3 {
  font-family: 'Verdana', sans-serif;
  font-size: 1em;
  color: darkblue;
  text-shadow: 0.03em 0.03em 0.01em #000;
  letter-spacing: 0.03em;
}