<?php
session_start();
$error='';
if (isset($_POST['submit'])) {
    if (empty($_POST['username']) || empty($_POST['password'])) {
        $error = "Username or Password is invalid";
    } else {
        $username = $_POST['username'];
        $password = $_POST['password'];
        $username = ($username);
        $password = ($password);
        if ($rows == 1) {
            $_SESSION['login_user'] = $username;
            header("location: profile.php");
        } else {
            $error = "Username or Password is invalid";

        }
    }
}