remove post html, js, css on insert into mysql

Question

When I post html, js, css tag, rule, syntax's on text input. it show's up on page result!
I user $conn->real_escape_string and mysqli prepared statement but still not secure for me.

my code is:

<?php
   require 'config/config.php';
   mysqli_set_charset($conn,"utf8");
$qmsg = $_POST["qsmsg"];
$qmsgs = mysqli_real_escape_string($conn, $qmsg);
$ansr = "Answer";
$userName = "John";
$userId="4";
$userType="user";
$imgsp="images/avatar.jpg";

$stmt = $conn->prepare("INSERT INTO qa (qus, ansrq, uname, uid, utype, uimage) VALUES (?, ?, ?, ?, ?, ?)");
$stmt->bind_param("sssiss", $qmsgs, $ansr, $userName, $userId, $userType, $imgsp);
...
$stmt->close();
$conn->close();
?>

Result on my page:

Answer 1

This is an XSS problem, not a database or CSS problem.

The quick answer is you must call htmlspecialchars on any user data that you're displaying in an HTML context. That will neutralize any HTML a user's introduced either deliberately or by accident.

The long answer is people like to be able to put in some formatting, so consider using something like Markdown so you can type things like *bold* and _italic_ and not have to write actual HTML. There are many, many PHP implementations of this readily available.