<?php
$servername = "localhost";
$username = "root";
$password = "tu_contraseÃ±a_de_mysql";
$dbname = "contraseÃ±as";

$conn = new mysqli($servername, $username, $password, $dbname);

if ($conn->connect_error) {
    die("Error en la conexiÃ³n: " . $conn->connect_error);
}

$usuario = $_POST['usuario'];
$contraseÃ±a = $_POST['contraseÃ±a'];

$sql = "SELECT * FROM usuarios WHERE usuario = ? AND contraseÃ±a = ?";
$stmt = $conn->prepare($sql);
$stmt->bind_param("ss", $usuario, $contraseÃ±a);
$stmt->execute();
$resultado = $stmt->get_result();

if ($resultado->num_rows > 0) {
    header("Location: destino.html");
} else {
    echo "Usuario o contraseÃ±a incorrectos";
}

$stmt->close();
$conn->close();
?>