Frame-able Wordpress.org Page

<?php

header("Content-Type: text/html; charset=utf-8");
require_once "wp-load.php";

date_default_timezone_set(get_option('timezone_string'));

// Get a specificed category
if (isset($_GET['cat'])) {
    $cat = get_category_by_slug($_GET['cat']);

    $cat_id = $cat->term_id;
} else {
    $cat_id = 0;
}

// Get the posts
$posts = wp_get_recent_posts(array(
    'numberposts' => 10,
    'offset' => 0,
    'category' => $cat_id,
    'orderby' => 'post_date',
    'order' => 'DESC',
    'post_type' => 'post',
    'post_status' => 'publish',
    'suppress_filters' => true,
));

?><!DOCTYPE html>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html;charset=utf-8" >

    <title><?= get_option('blogname') ?> - Recent Posts | <?= get_option('blogdescription') ?></title>

    <link rel="stylesheet" type="text/css" media="all" href="<?= get_stylesheet_directory_uri() ?>/style.css" />
    <style type="text/css">
    body {
        background: #FFF;
    }

    .gallery-size-thumbnail {
        display: none;
    }
    </style>
</head>
<body>
<div id="posts">
<?php
foreach ($posts as $post) {
    $permalink = get_permalink($post['ID']);
    $post_time = strtotime($post['post_date']);
    $post_author = get_userdata($post['post_author']);
?>
    <article id="post-<?= $post['ID'] ?>" class="post-<?= $post['ID'] ?> post type-post status-publish format-standard hentry category-community tag-hunger tag-rotary-club tag-winthrop-rotary-club">
        <header>
            <h1 class="entry-title"><a href="<?= $permalink ?>" title="<?= $post['post_title'] ?>" rel="bookmark"><?= $post['post_title'] ?></a></h1>
            <div class="entry-meta">
                <span class="sep">Posted on </span>
                <a href="<?= $permalink ?>" title="<?= date('g:i a', $post_time) ?>" rel="bookmark"><time class="entry-date" datetime="<?= date(DateTime::ATOM, $post_time) ?>"><?= date('F j, Y', $post_time) ?></time></a>
                <span class="by-author"> <span class="sep"> by </span> <span class="author vcard"><a class="url fn n" href="<?= get_author_posts_url($post['post_author']) ?>" title="View all posts by <?= $post_author->display_name ?>" rel="author"><?= $post_author->display_name ?></a></span></span>
            </div>
        </header>
        <div class="entry-content"><?= apply_filters('the_content', $post['post_content']) ?></div>
    </article>
<?php } ?>
</div>
</body>
</html>