Código PHP:
<?php if (isset ($_POST["envia_consulta"])){ ?>
<?php
$d = $_POST['dia'];
$m = $_POST['mes'];
$a = $_POST['agno'];
$nacimiento= "$d-$m-$a";
$aries_ini="21/03/$a";
$aries_fin="20/04/$a";
$tauro_ini="21/04/$a";
$tauro_fin="21/05/$a";
$geminis_ini="22/05/$a";
$geminis_fin="21/06/$a";
?>
<?php
if ("$nacimiento >= $aries_ini" && "$nacimiento <= $aries_fin"){
$zodiaco="1";
include("zodiaco.php");}
elseif ("$nacimiento >= $tauro_ini" && "$nacimiento <= $tauro_fin"){
$zodiaco="2";
echo "verdad";
include("zodiaco.php");}
elseif ("$nacimiento >= $geminis_ini" && "$nacimiento <= $geminis_fin"){
$zodiaco="3";
include("zodiaco.php");}
else { echo "no se han encontrado coincidencias";}
}?>