This prompt helps AI models like Claude generate a real WordPress Full Site Editing (FSE) theme, not just a collection of HTML files that look like a website.
It instructs the AI to build a production-ready theme using modern WordPress best practices, including proper theme.json configuration, reusable block patterns, clean file organization, separate CSS, valid Gutenberg block serialization, and a meaningful level of customization through the WordPress Site Editor.
The goal is to create a theme that is:
- Installable in WordPress
- Compatible with Full Site Editing
- Free of Gutenberg block validation errors
- Easy to customize through the Site Editor
- Organized using clean, maintainable code
- Built with a professional architecture instead of relying on inline styles or hardcoded layouts
While no AI prompt can guarantee perfect results every time, this prompt provides a strong foundation for generating high-quality WordPress themes. If additional refinements are needed, you can continue working with Claude, ChatGPT, Codex, or another AI coding assistant to customize the design, add features, or improve the architecture.
Tip: This prompt is designed to get you most of the way there. Think of AI as your development partner—not a one-click solution. Generate the theme, test it in WordPress, then continue refining it with AI until it matches your exact vision.
WordPress Full Site Editing Demo Theme – Pet Grooming Landing Page
Create a complete WordPress Block Theme (Full Site Editing) named Happy Paws Grooming.
This project is intended to demonstrate both modern WordPress Full Site Editing architecture and high-quality visual design.
The final result should resemble a commercially distributed premium WordPress theme rather than a simple AI-generated landing page.
The theme should be a real FSE theme, not a classic hardcoded landing page disguised as a block theme.
Goal
Build a modern, responsive one-page website for a fictional pet grooming business.
Do NOT build additional pages.
The homepage should include only:
Hero
Services
Why Choose Us
Before & After Gallery
Testimonials
Call To Action
Footer
Keep the design elegant, warm, premium, and friendly.
Technical Requirements
This must be a real WordPress Block Theme.
Use Full Site Editing.
Use this structure:
happy-paws/
style.css
theme.json
functions.php
screenshot.png
/templates
front-page.html
index.html
/parts
header.html
footer.html
/patterns
hero.php
services.php
why-us.php
gallery.php
testimonials.php
cta.php
/assets
/css
styles.css
/images
Everything should be importable into WordPress as a normal installable theme.
CSS Rules
Very important:
Do NOT use inline CSS.
Do NOT place style="" attributes anywhere.
Do NOT generate large CSS blocks inside templates, template parts, or patterns.
Store all custom styling inside:
assets/css/styles.css
Only enqueue this stylesheet through functions.php.
Keep CSS organized with comments such as:
/* Hero */
/* Buttons */
/* Services */
/* Gallery */
/* Testimonials */
/* CTA */
/* Footer */
/* Responsive */
CSS should handle advanced presentation and responsive behavior, not basic design tokens that belong in theme.json.
FSE Customization Requirements
This theme must be meaningfully customizable through the WordPress Site Editor.
Do not make the design system CSS-dominant.
Expose appropriate design tokens through theme.json.
Users should be able to customize the following through the Site Editor wherever practical:
primary color
accent color
background color
surface/card color
heading color
body text color
muted text color
link color
button colors
font families
font sizes
line heights
content width
wide width
spacing scale
block gap
border radius
button styling
Use WordPress preset variables in assets/css/styles.css.
Example:
background: var(--wp--preset--color--primary);
color: var(--wp--preset--color--dark);
Avoid hardcoded hex colors in CSS when the value represents a user-configurable design token.
Bad:
background: #5B7CFA;
color: #202124;
Good:
background: var(--wp--preset--color--primary);
color: var(--wp--preset--color--dark);
Hardcoded colors are acceptable only for intentional decorative effects, shadows, overlays, or fixed design details that should not be user-editable.
Avoid unnecessary !important.
Only use !important when absolutely required to override WordPress core output.
Theme.json Requirements
Use theme.json properly as the design-token layer.
Define:
color palette
typography presets
font families
font sizes
line heights
spacing presets
layout widths
border radius
shadow presets where supported
global body styles
global heading styles
global paragraph styles
global link styles
global button styles
block defaults where appropriate
Use theme.json first.
Use CSS only when theme.json cannot express the design cleanly.
What Belongs In CSS
Keep the following CSS-driven:
responsive layouts
flex/grid implementation
sticky header behavior
mobile navigation behavior
pseudo-elements
hover transforms
gallery overlays
animations
decorative gradients
advanced positioning
image aspect ratios
object-fit rules
Design Style
Modern.
Premium.
Clean.
Lots of whitespace.
Rounded corners.
Soft shadows.
Large photography.
Subtle gradients.
Friendly typography.
Nothing flashy.
The business should feel trustworthy and upscale.
Color Palette
Define these in theme.json and reference them with WordPress preset variables.
Primary:
#5B7CFA
Accent:
#FFB547
Background:
#FAFAFA
Dark Text:
#202124
Muted Text:
#6B7280
Surface/Card:
#FFFFFF
Also include any additional light background or support colors as named palette values if used by the design.
Fonts
Headings:
Poppins
Body:
Inter
Configure these in theme.json.
Sections
Hero
Large headline.
Example:
Professional Grooming For Happy Pets
Supporting text.
Two buttons:
Book Appointment
View Services
Large dog image on the right.
Services
Four cards:
Dog Bath
Full Groom
Nail Trimming
Spa Package
Each card should include:
simple icon
title
short description
Why Choose Us
Three feature cards.
Examples:
Certified Groomers
Gentle Care
Convenient Scheduling
Before & After Gallery
Simple four-image responsive grid using placeholder images.
Testimonials
Three testimonial cards.
Each should include:
customer name
pet name
five stars
testimonial text
CTA
Large centered section.
Headline.
Button:
Schedule Your Visit
Footer
Include:
logo
phone
email
address
social icons
copyright
Responsiveness
Fully responsive.
Must work on:
desktop
tablet
mobile
Use modern CSS.
Avoid unnecessary wrappers.
Code Quality
Write clean production-quality code.
Use semantic HTML.
Keep markup organized.
Avoid duplicated CSS.
Keep CSS maintainable.
Use meaningful class names.
Use core Gutenberg blocks wherever possible.
WordPress Best Practices
Use block patterns wherever appropriate.
Follow WordPress coding standards.
Use proper enqueueing.
Do not hardcode unnecessary values.
Do not install plugins.
Do not use page builders.
No Bootstrap.
No Tailwind.
No jQuery.
No inline JavaScript.
No inline CSS.
Images
Use obvious placeholder image references with descriptive filenames such as:
hero-dog.jpg
before-after-1.jpg
testimonial-dog.jpg
Do not embed base64 images.
Gutenberg Serialization Requirements — Critical
This theme must be fully compatible with the WordPress Site Editor.
Do not generate HTML that merely renders correctly.
Generate valid serialized Gutenberg block markup.
Requirements:
Every block must use proper <!-- wp: --> serialization.
Every opening block comment must have the correct closing block comment.
Every block JSON object must be valid.
Never manually add attributes to rendered HTML that are not declared in the block JSON.
If a Group block renders <section id="services">, the block comment must declare "anchor":"services".
If using <section>, declare "tagName":"section".
Never manually insert id="" attributes that are not represented as block attributes.
Never insert ordinary HTML comments such as <!-- Hero Section --> inside serialized Gutenberg block trees.
Do not manually alter Gutenberg-generated markup after creating a block.
Patterns must consist of valid serialized core block markup, not arbitrary HTML that resembles blocks.
The Site Editor must open with zero "Block contains unexpected or invalid content" warnings.
Architecture Philosophy
Think like a senior WordPress theme engineer.
Do not simply create a beautiful website.
Create a commercially distributable WordPress Full Site Editing theme.
The architecture should reflect what an experienced WordPress theme developer would ship to customers.
Prioritize the following in this order:
WordPress best practices
Gutenberg compatibility
Clean architecture
Long-term maintainability
Meaningful Site Editor customization
Performance
Accessibility
Beautiful visual design
The Site Editor should own the global design system.
theme.json should define as much of the design system as WordPress supports, including:
colors
typography
spacing
layout widths
border radius
shadows where supported
button defaults
heading defaults
paragraph defaults
block defaults
styles.css should primarily handle:
responsive layouts
advanced presentation
animations
hover effects
pseudo-elements
gradients
overlays
sticky header behavior
positioning
behavior not currently supported by theme.json
Avoid creating a classic hardcoded theme wrapped in Gutenberg blocks.
Use CSS to enhance the design—not to replace the design system.
Build the theme as if it were intended for commercial distribution in the WordPress ecosystem.
Final Validation Checklist
Before completing the theme, verify:
theme.json is valid JSON.
Every PHP file parses successfully.
Every template loads correctly.
Every pattern loads correctly.
Every <!-- wp: --> block has a matching closing block comment.
Every serialized block JSON object is valid.
Every section ID is represented by a proper Gutenberg anchor attribute.
No ordinary HTML comments exist inside serialized block trees.
No style="" attributes exist anywhere.
All custom CSS is in assets/css/styles.css.
Hardcoded CSS colors are minimized.
User-configurable colors use WordPress preset variables.
Unnecessary !important declarations are avoided.
Site Editor color controls affect the appropriate areas.
Site Editor typography controls work where practical.
Button customization works where practical.
The frontend renders correctly.
The WordPress Site Editor renders correctly.
There are zero "Block contains unexpected or invalid content" warnings.
Deliverable
Generate a complete importable WordPress Block Theme that can be zipped, installed, activated, and immediately display the finished one-page website.
Prioritize:
clean architecture
maintainability
Gutenberg compatibility
meaningful Site Editor customization
WordPress best practices
polished visual design
Do not prioritize unnecessary features.
The theme is not considered complete simply because the frontend looks correct.
The project is complete only when:
the theme installs cleanly
the Site Editor opens without block validation warnings
users can meaningfully customize the design through the Site Editor
the frontend and Site Editor remain visually consistent
theme.json owns the global design system
CSS primarily handles advanced presentation
the architecture follows modern WordPress Full Site Editing best practices
the code is suitable for long-term maintenance and commercial distribution