<div class="col-md-6">

                    <div class="contact_from">
                        <form name="mail-form">
                            <div class="contact_input_area">
                                <div class="row">
                                    <div class="col-md-12">
                                        <div class="form-group">
                                            <input type="text" class="form-control mail-form-name" name="name" id="name" placeholder="Your Name" required>
                                            <span class="pull-right alert-error"></span>
                                        </div>
                                    </div>

                                    <div class="col-md-12">
                                        <div class="form-group">
                                            <input type="email" class="form-control mail-form-email" name="email" id="email" placeholder="Your E-mail" required>
                                            <span class="pull-right alert-error"></span>
                                        </div>
                                    </div>

                                    <div class="col-12">
                                        <div class="form-group">
                                            <textarea name="message" class="form-control mail-form-message" id="message" cols="30" rows="4" placeholder="Your Message *" required></textarea>
                                            <span class="pull-right alert-error"></span>
                                        </div>
                                    </div>
                                    <div class="col-12">
                                        <input  type="submit" class="btn submit-btn mail-form-button" value="Send">
                                    </div>
                                </div>
                            </div>
                        </form>
                    </div>
                </div>

<?php
include_once ('connect.php');

if(!$conn){
    die ("connection failed:".mysqli__connect_error());
}

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $entityBody = file_get_contents('php://input');
    $encoded = json_decode($entityBody, true);

    if (!empty($encoded['email'])) {

        $email = $encoded['email'];
        $name = $encoded['name'];
        $message = $encoded['message'];

        mysqli_set_charset($conn,"utf8");
        $sql = "INSERT INTO `mail` (`name`,`email`,`message`) values('$name','$email','$message')";
        if(mysqli_query($conn,$sql)){
            $response['success'] = 1;

        }else{
            $response['success'] = 0;
        }
        echo json_encode($response);
    }
}
?>

<?php
$server = "localhost";
$user = "root";
$pass = "qwe4444";
$dbname = "qwe";
$conn = mysqli_connect($server,$user,$pass,$dbname);