CSS Nesting is a native CSS feature that allows you to nest style rules inside one another, similar to how preprocessors like Sass and Less work. Using the & symbol to reference the parent selector, you can write more organized, readable stylesheets without needing a build step. It's supported in Chrome 120+, Edge 120+, Safari 17.2+, and Firefox 117+.

The & (ampersand) is a placeholder that represents the parent selector in nested CSS rules. For example, &:hover inside .button { } compiles to .button:hover. You can also place it after a selector like .card { &__title { } } which becomes .card__title, enabling BEM-style naming.

Native CSS Nesting is supported in all major modern browsers: Chrome 120+, Edge 120+, Safari 17.2+, Firefox 117+, Opera 106+, and Samsung Internet 25+. As of 2024, global support exceeds 90% of users. For older browsers, you can use this tool to compile nested CSS into flat, compatible CSS.

Yes! Native CSS Nesting allows you to nest @media and @supports queries directly inside style rules. For example, .sidebar { width: 100%; @media (min-width: 768px) { width: 300px; } } will apply the width:300px only on larger screens. This keeps related responsive styles together.

While similar, there are key differences: (1) Native CSS Nesting requires the & symbol more explicitly — you can't just write a descendant selector without & in front (though some browsers may relax this). (2) Native nesting doesn't support Sass features like @extend, mixins, or variables (use CSS custom properties instead). (3) Native nesting is parsed by the browser directly, with no compilation needed.

This playground handles the vast majority of real-world nesting patterns accurately — including & parent references, pseudo-classes, pseudo-elements, BEM-style concatenation, multi-level nesting, and @media/@supports at-rules. For edge cases or extremely complex nested structures, we recommend verifying against the official W3C CSS Nesting Specification.