WordPress 7.1 brings responsive styles into Core. Editors can define mobile and tablet values in Global Styles or on an individual block, while themes can configure breakpoints through settings.viewport in theme.json.
Why it matters
Spacing that works on desktop can be reduced on mobile without writing a media query for every case. Blocks using standard block supports receive responsive handling for common properties such as spacing, dimensions, and color, keeping the decision inside the design system instead of scattered CSS.
The feature does not repair an old design automatically. Custom controls in a bespoke block may not support responsive states, and changing breakpoints can affect many pages. The editor canvas is still a preview that must be compared with real browser and device output.
Try it quickly
Choose one Group block and change only its mobile padding. Inspect the result at 320, 390, and 768 pixels in both Arabic and English. Review the generated CSS before applying the setting across the theme.
For the complete release process, read the WordPress 7.1 upgrade guide. Source: the August 2026 developer update.