Performance and CSS guide
Read complete guidance on rendering cost, bundle size, and architecture.
Performance
Summary Page
Performance-first CSS
CSS architecture affects maintainability, rendering behaviour, and long-term performance.
This page is a summary. For full guidance, use Performance and CSS.
- reduce unused CSS
- split CSS by responsibility
- avoid giant global stylesheets
- prefer static-first rendering
- avoid framework CSS overhead where unnecessary
- keep selectors predictable
- contain legacy CSS
Most CSS performance problems in production systems come from scale, architecture, and maintainability rather than raw selector speed.