// control de ancho de columna principal
if($page['sidebar_first'] && !$page['sidebar_second']) { //col izq+central
$columna_principal_class = ' class="esquema-2-col-ic"';
} elseif(!$page['sidebar_first'] && $page['sidebar_second']) { //col central+der
$columna_principal_class = ' class="esquema-2-col-cd"';
} elseif(!$page['sidebar_first'] && !$page['sidebar_second']) { // 1 columna
$columna_principal_class = ' class="esquema-1-col"';
} elseif($page['sidebar_first'] && $page['sidebar_second']) { // 3 columnas
$columna_principal_class = ' class="esquema-3-col"';
}// fin control
?>