Untitled

<!DOCTYPE html>
<html>
<head>
    <title>Title</title>
    <link rel="stylesheet" href="notyf/notyf.min.css">
</head>
<body>
    <form action="" method="POST">
        <input type="text" name="user"/>
        <input type="text" name="pass"/>
        <button type="submit" onclick="myFunc()" name="submit">Register</button>
    </form>

    <?php
        if (isset($_POST["submit"])) {
            if (!empty($_POST["user"]) && !empty($_POST["pass"])) {
                $user = $_POST["user"];
                $pass = $_POST["pass"];
                $conn = new mysqli("localhost", "root", "") or die (mysqli_error());
                $db = mysqli_select_db($conn, "toast") or die ("DB Error!");
                $query = mysqli_query($conn, "SELECT * FROM user WHERE user='".$user."'");
                $numrows = mysqli_num_rows($query);
                if ($numrows == 0) {
                    $sql = "INSERT INTO user(user, pass) VALUES('$user', '$pass')";
                    $result = mysqli_query($conn, $sql);
                    if ($result) {
                        echo "<script src='notyf/notyf.min.js'></script>";
                        echo "<script>";
                        echo    "function myFunc() {";
                        echo        "var notyf = new Notyf();";
                        echo        "notyf.confirm('Success!');";
                        echo    "}";
                        echo "</script>";
                    } else {
                        echo "Failure!";
                    }
                } else {
                    echo "Already exist! Please try again.";
                }
            }
        }
    ?>
</body>
</html>