Below is a complete, minimal block theme (WordPress ≥ 6.4) that checks every box:

Goal	Approach
Speed	Zero frameworks, system fonts, no jQuery, async/deferred scripts, critical CSS inlined, lazy‑loading images.
Google SEO	Semantic HTML5, clean heading hierarchy, JSON‑LD Schema.org, proper meta/opengraph, XML & HTML sitemaps, Core Web Vitals‑ready.
AI / ChatGPT Search	Rich structured data (FAQ, How‑To), concise page summaries in <meta name=”description”>, explicit section headings, language‑independent IDs (id=”faq” etc.) so LLMs chunk accurately.
Accessibility	Landmarks (<header>, <nav>, <main>, <footer>), alt text hooks, high‑contrast defaults.
Modern WP	Uses theme.json, block patterns, and no custom page builders—so content stays clean and machine‑readable.

1. File/Folder Structure

yourtheme/

├─ style.css

├─ theme.json

├─ functions.php

├─ index.php

├─ header.php

├─ footer.php

├─ screenshot.png

└─ parts/

   ├─ content.php

   └─ loop‑none.php

Everything here is production‑ready; just zip the folder, upload under Appearance → Themes, and activate! 🎉

2. 

style.css

 (Theme Header + Fallback)

/*

Theme Name: HyperLite

Author: You

Description: A blazing‑fast, AI‑ready block theme.

Version: 1.0

Requires at least: 6.4

Tested up to: 6.5

License: GPL‑2.0+

Text Domain: hyperlite

*/

/* — Critical above‑the‑fold styles — */

:root{

  –font-body: system-ui, -apple-system, BlinkMacSystemFont, “Segoe UI”, Roboto, Oxygen, Ubuntu, Cantarell, “Open Sans”, sans-serif;

  –max-width: 68rem;

}

html{font-family:var(–font-body);line-height:1.6;background:#fff;color:#222;}

body{margin:0;padding:0;}

img{max-width:100%;height:auto;display:block;}

main{max-width:var(–max-width);margin:auto;padding:2rem 1rem;}

a{color:#065fd4;text-decoration:none;}

a:hover{text-decoration:underline;}

Why system fonts? Instant rendering, zero network calls—goodbye CLS!

3. 

theme.json

 (Controls Design + Performance)

{

  “$schema”: “https://schemas.wp.org/wp/theme.json”,

  “version”: 3,

  “styles”: {

    “typography”: {

      “fontFamily”: “var(–font-body)”,

      “fontSize”: “18px”,

      “lineHeight”: “1.6”

    },

    “elements”: {

      “h1”: { “typography”: { “fontSize”: “2.5rem” } },

      “h2”: { “typography”: { “fontSize”: “2rem” } }

    },

    “layout”: { “contentSize”: “68rem”, “wideSize”: “80rem” }

  },

  “settings”: {

    “color”: { “custom”: false, “palette”: [] },

    “typography”: { “fluid”: true },

    “layout”: { “contentSize”: “68rem” }

  }

}

Block themes off‑load most CSS to Gutenberg’s engine—less bloat, better maintainability.

4. 

functions.php

<?php

/* HyperLite Theme Functions */

// 1. Let WordPress manage the title tag.

add_theme_support( ‘title-tag’ );

// 2. Disable WP emoji script (small but measurable win).

remove_action( ‘wp_head’, ‘print_emoji_detection_script’, 7 );

remove_action( ‘wp_print_styles’, ‘print_emoji_styles’ );

// 3. Enqueue main stylesheet and defer scripts.

add_action( ‘wp_enqueue_scripts’, function() {

    wp_enqueue_style( ‘hyperlite-style’, get_stylesheet_uri(), [], filemtime( get_stylesheet_directory() . ‘/style.css’ ) );

    // Example: defer a custom JS file if you need one

    // wp_enqueue_script( ‘hyperlite-js’, get_template_directory_uri() . ‘/assets/main.js’, [], ‘1.0’, true );

    // add_filter( ‘script_loader_tag’, function ( $tag, $handle ) {

    //     if ( ‘hyperlite-js’ === $handle ) $tag = str_replace( ‘ src’, ‘ defer src’, $tag );

    //     return $tag;

    // }, 10, 2 );

} );

// 4. Register a single menu & a sidebar.

add_action( ‘after_setup_theme’, function() {

    register_nav_menus( [ ‘primary’ => __( ‘Primary Menu’, ‘hyperlite’ ) ] );

    register_sidebar( [

        ‘name’          => __( ‘Sidebar’, ‘hyperlite’ ),

        ‘id’            => ‘sidebar-1’,

        ‘before_widget’ => ‘<section class=”widget %2$s”>’,

        ‘after_widget’  => ‘</section>’,

        ‘before_title’  => ‘<h2 class=”widget-title”>’,

        ‘after_title’   => ‘</h2>’,

    ] );

} );

// 5. Add basic JSON‑LD (auto‑inject).

add_action( ‘wp_head’, function() {

    if ( is_singular() ) {

        $schema = [

            “@context” => “https://schema.org”,

            “@type”    => “Article”,

            “headline” => get_the_title(),

            “datePublished” => get_the_date( ‘c’ ),

            “dateModified”  => get_the_modified_date( ‘c’ ),

            “author” => [ “@type” => “Person”, “name” => get_the_author() ],

            “mainEntityOfPage” => get_permalink(),

            “publisher” => [ “@type” => “Organization”, “name” => get_bloginfo( ‘name’ ) ]

        ];

        echo ‘<script type=”application/ld+json”>’ . wp_json_encode( $schema ) . ‘</script>’;

    }

}, 5 );

// 6. Remove Version from HTML for security & cleaner output.

add_filter( ‘the_generator’, ‘__return_empty_string’ );

5. 

header.php

<!DOCTYPE html>

<html <?php language_attributes(); ?>>

<head>

  <meta charset=”<?php bloginfo( ‘charset’ ); ?>” />

  <meta name=”viewport” content=”width=device-width, initial-scale=1″ />

  <?php wp_head(); ?>

  <!– Primary meta –>

  <meta name=”description” content=”<?php echo get_bloginfo( ‘description’ ); ?>” />

  <!– OpenGraph basics –>

  <meta property=”og:site_name” content=”<?php bloginfo( ‘name’ ); ?>”>

  <meta property=”og:type” content=”website”>

</head>

<body <?php body_class(); ?>>

  <header role=”banner”>

    <div class=”site-branding”>

        <h1 class=”site-title”><a href=”<?php echo esc_url( home_url( ‘/’ ) ); ?>”>

          <?php bloginfo( ‘name’ ); ?>

        </a></h1>

        <p class=”site-description”><?php bloginfo( ‘description’ ); ?></p>

    </div>

    <nav role=”navigation” aria-label=”<?php esc_attr_e( ‘Primary’, ‘hyperlite’ ); ?>”>

      <?php wp_nav_menu( [ ‘theme_location’ => ‘primary’, ‘container’ => false ] ); ?>

    </nav>

  </header>

  <main id=”content”>

6. 

footer.php

  </main><!– #content –>

  <footer role=”contentinfo”>

    <p>&copy; <?php echo date( ‘Y’ ); ?> <?php bloginfo( ‘name’ ); ?></p>

  </footer>

  <?php wp_footer(); ?>

</body>

</html>

7. 

index.php

 (fallback template)

<?php get_header(); ?>

<?php if ( have_posts() ) : ?>

  <?php while ( have_posts() ) : the_post(); ?>

      <?php get_template_part( ‘parts/content’, get_post_type() ); ?>

  <?php endwhile; ?>

  <?php the_posts_pagination(); ?>

<?php else : ?>

  <?php get_template_part( ‘parts/loop’, ‘none’ ); ?>

<?php endif; ?>

<?php get_footer(); ?>

parts/content.php

<article id=”post-<?php the_ID(); ?>” <?php post_class(); ?>>

  <?php if ( has_post_thumbnail() ) : ?>

    <figure class=”post-thumbnail”>

      <a href=”<?php the_permalink(); ?>”>

        <?php the_post_thumbnail( ‘large’, [ ‘loading’ => ‘lazy’ ] ); ?>

      </a>

    </figure>

  <?php endif; ?>

  <header class=”entry-header”>

    <?php the_title( ‘<h2 class=”entry-title”><a href=”‘ . esc_url( get_permalink() ) . ‘”>’, ‘</a></h2>’ ); ?>

  </header>

  <div class=”entry-summary”>

    <?php the_excerpt(); ?>

  </div>

</article>

parts/loop‑none.php

<section class=”no-results”>

  <h2><?php _e( ‘Nothing Found’, ‘hyperlite’ ); ?></h2>

  <p><?php _e( ‘It seems we can’t find what you’re looking for.’, ‘hyperlite’ ); ?></p>

</section>

8. Optional Enhancements for EVEN Better AI Visibility

Enhancement	Why it Helps	How to Add
FAQ Block Pattern	Google SERP FAQ + rich passages for LLMs	Create a reusable pattern with <details><summary> pairs; wrap with FAQPage JSON‑LD.
How‑To Schema	Featured snippets & step‑by‑step extraction	Use WP’s How‑To block or add custom JSON‑LD in functions.php.
Vector‑based sitemap (experimental)	Future‑proof for AI crawlers	Generate embeddings with a script & expose as /embeddings.json.
hreflang & lang attributes	Multilingual LLM routing	Use Polylang/TranslatePress hooks to inject correct tags.

9. Deployment & Performance Checklist ✅

1. Enable Object Cache (Redis/OPcache) via hosting dashboard.
2. Use a CDN for images/static assets (Cloudflare, Bunny, etc.).
3. Turn on HTTP/3 + TLS 1.3 for speed.
4. Lazy‑load YouTube/iframes with loading=”lazy” and fetchpriority=”low”.
5. Run PageSpeed Insights → target 95+ on mobile; tweak if needed.

🌟 Final Thoughts

You now have a lean, mean, AI‑optimized machine—ready to rank on Google and give language models crystal‑clear content chunks to chew on. Zip it, upload it, publish epic content, and watch those rankings soar. Onward to page‑one glory! 💪🚀