fse-block-theme-development

Build a block theme by establishing a design-system-first workflow that codifies colors, typography, and spacing into theme.json tokens. This approach drives layout through templates and template parts rather than hardcoding styles, ensuring reproducible styling and accessibility across the site.

An FSE block theme requires a minimal root structure under themes/theme-name/ containing style.css, theme.json, and templates/index.html. The index.html file serves as the ultimate fallback template, while theme.json manages the design tokens for the entire theme.

Migrate a classic theme to Full Site Editing by refactoring hardcoded styles into theme.json design tokens and converting traditional PHP templates into block-based templates and template parts. This establishes a token-driven styling workflow that enables style variations and accessibility compliance.

Create style variations across multiple templates and blocks by leveraging token-driven styling within theme.json. By codifying design tokens for colors, typography, and spacing, you can iterate on style variations globally without hardcoding values into individual templates.

Use design tokens instead of hardcoded styles to ensure accessibility and maintainability across block patterns. Codifying values into theme.json creates a reproducible workflow that prevents style duplication, enables easy style variations, and enforces a consistent design system throughout the theme.

FSE block theme development enforces token-driven styling to avoid hardcoding CSS values. When styles are hardcoded directly in templates or block patterns, the theme.json design system is bypassed, breaking style variations and reproducibility across the site.