Untitled

$header = template('header', ['title' => 'Hello World!']);
$content = template('content', ['content' => "Lorem ipsum...", 'meta' => 'Author info']);
$footer = template('footer', ['copy' => "Copyright ". date('Y')]);

// ...skipped logic

echo $header, $content, $footer;

/**
 * @param  string $template
 * @param  array  $vars
 * @return string
 */
function template($template, $vars) {
    // place your code here
    // ...
}

!-- header.phtml -->
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title><?=$title?></title>
</head>
<body>
<!-- content.phtml -->
<div class="container">
    <p><?=$content?></p>
    <p><?=$meta?></p>
</div>
<!-- footer.phtml -->
<footer>
    <?=$copy?>
</footer>
</body>
</html>