div#centro {float:left; width:74%; text-align:left; margin:1ex 0 0 2%;}

div#colizq {float:left; width:65%; background:#fff; margin:0.1ex 0 0 0;}
.contenido3 {color:#3E454D; padding:0.5ex;}
.conmargen {margin:0 0.3ex 0 0.3ex;}

div#colder {float:left; width:35%; text-align:center; background:#eef0f2; margin:0.1ex 0 0 0;}
.contenido4 {color:#3E454D; padding:0.5ex;}
.contenido4 a{color:#3E454D; text-decoration:none;}
.contenido4 a:hover{color:#3E454D; text-decoration:underline;}

.relac {background:#3E454D; color:#eef0f2;}

.intro {background:#fff; border:0; margin:0.1ex 0.2ex 0 0.2ex; padding:0.5ex;}