comment form i mysql

Code:
<!DOCTYPE html>
<html>
    <head>
        <title>Test komentari</title>
        <style type="text/css">
            body {
                background: gray;
            }
        </style>
    </head>
    <body>
<?php

    $mysqli = new mysqli("localhost", "username", "password", "komentari");
    
    if ($mysqli->connect_errno) {
        printf("Connect failed: %s\n", $mysqli->connect_error);
        exit();
    }

    if (isset($_POST['komentar'])) {
        if ($stmt = $mysqli->prepare("INSERT INTO komentari (komentar, ime, vrijeme) VALUES (?, ?, NOW())")) {

            $stmt->bind_param("ss", $_POST['komentar'], $_POST['ime']);
            $stmt->execute();

            $stmt->close();
        }        
    }
?>
        <form action="index.php" method="POST">
            <input type="text" name="ime" /><br/>
            <textarea name="komentar" rows="10"></textarea>
            <br/>
            <input type="submit" name="Submit" value="Send" />
        </form>
        <br/>
        <br/>
<?php
if ($result = $mysqli->query("SELECT komentar, ime, DATE_FORMAT(vrijeme, '%d.%m.%Y %H:%i:%S') AS tacno FROM komentari ORDER BY vrijeme DESC")) {

        while ($row = $result->fetch_assoc()) {
            if ($row['komentar']) {    
?>
        <hr style="clear: both"/>
        <p style="float: left"><?=$row['komentar']?><p/>
        <p style="float: right">Vaše ime: <?=$row['ime']?><br/><?=$row['tacno']?><p/>
<?php
            }

        }


    $result->free();
}


    $mysqli->close();
?>
    </body>
</html>