PESQUISA CEP MYSQL E AJAX

/*BY: ASK JARVIS + DANTE TESTA */


<?php

$cep = $_POST['cep'];

$conexao = mysqli_connect('localhost', 'user', 'senha', 'ceps');

$query = "SELECT * FROM ceps WHERE cep = '$cep'";

$result = mysqli_query($conexao, $query);

if(mysqli_num_rows($result) > 0){
    echo 'true';
}else{
    echo 'false';
}

?>


<input type="text" id="cep" size="20">
<input type="button" id="validar" value="Consultar CEP">
<script>
jQuery('#validar').click(function(){

 var cep = jQuery('#cep').val().replace(/\D/g, '');

    if(cep.length == 8){
        jQuery.ajax({
            url: 'https://velozen.com.br/pesquisa-cep.php',
            type: 'POST',
            data: {cep: cep},
            success: function(data){
                if(data == 'true'){
                    jQuery('.sim').css('display','block');
                    jQuery('.nao, .info').css('display','none');
                }else{
                    jQuery('.nao').css('display','block');
                    jQuery('.sim, .info').css('display','none');
                }
            }
        });
    }else{
       jQuery('.info').css('display','block');
       jQuery('.nao, .sim').css('display','none');
    }
});
</script>


<style>
    .sim,    .nao,    .info {
        display: none;
    }


    #cep {
        font-size: 22px;
        border: 1px solid #999999;
        padding: 10px;
        font-weight: bold;
        color: #333333;
    }

    #validar {
        font-size: 17px;
        border: 0px solid black;
        padding: 10px;
        background: #61CE70;
        color: white;        
        margin: 15px 0 0 0;
    }

    #validar:hover {
        background: black;
        color: white;
    }
</style>