Browser Support

Bullframe CSS targets browsers covered by the Browserslist query in .browserslistrc: defaults. Autoprefixer uses that same query when building CSS. Prefixes are added where needed; there are no polyfills for unsupported CSS APIs.

Builds

All seven builds (default / classless / utilities / dark / system-default) are intended for that defaults audience. They rely on:

• CSS custom properties (--bf-*)
• Flexbox and CSS Grid
• prefers-color-scheme (system-default builds)
• Modern rgb() color syntax
• Progressive enhancements gated with @supports where needed (for example range styling and some form/dialog polish)

Optional enhancements in the default pipeline (UA+ layer) use @supports / prefers-reduced-motion so older engines keep usable native UI.

Mobile

Tested against current Chromium and WebKit mobile. Forms (select, range) and <dialog> are the most engine-specific surfaces; spot-check iOS Safari when shipping custom form chrome.

Accessibility preferences

• prefers-reduced-motion: dialog enter transitions are skipped when reduced motion is requested
• forced-colors / high contrast: marked text and related rules adapt under Windows forced colors where implemented

Checking support

Inspect .browserslistrc and browsersl.ist for the live coverage of defaults.