<?php

include 'db_connect.php';

$username = isset($_POST['username']) ? $_POST['username'] : "";
$pass = isset($_POST['pass']) ? $_POST['pass'] : "";

$sql = "SELECT * FROM users WHERE username = '$username' AND pass = '$pass'";

$result = mysqli_query($conn, $sql);

if($row = mysqli_fetch_assoc($result)) {
    echo "You are logged";
} else {
    echo "Your login or password is incorrect";
}