HTML Link & Heading Extractor
About CSS @supports Generator
The CSS Feature Query (`@supports`) Builder creates robust `@supports (property: value)` rules to test browser feature capabilities (e.g. `subgrid`, `backdrop-filter`, `accent-color`, `anchor-name`, `field-sizing`) with logical `and`, `or`, and `not` fallback structures.
How to Use CSS @supports Generator
Step 1
Select a feature preset or enter custom CSS property/value pair.
Step 2
Configure logical combinators (`and`, `or`, `not`) if testing multiple features.
Step 3
Review the progressive enhancement CSS block.
Step 4
Click "Copy CSS".
Practical Use Cases for CSS @supports Generator
Progressive Enhancement for Modern CSS Features
Provide modern CSS Grid `subgrid` or `backdrop-filter: blur(10px)` styles for cutting-edge browsers while delivering clean static fallbacks for older engines.
Testing Selector Support with `@supports selector(...)`
Test whether a browser supports modern CSS selectors like `:has()` or `:is()` before applying advanced styling rules.
Input & Output Examples
Generating `@supports` for Glassmorphism Backdrop Filter
Feature: `backdrop-filter: blur(10px)` with fallback background
`.card { background: rgba(15, 23, 42, 0.95); }\n@supports (backdrop-filter: blur(10px)) {\n .card { background: rgba(15, 23, 42, 0.7); backdrop-filter: blur(10px); }\n}`Key Features & Performance
- ✓Presets for modern CSS features: `subgrid`, `backdrop-filter`, `accent-color`, `:has()`, `color-mix()`, `contain-intrinsic-size`, `view-transition-name`.
- ✓Supports logical operators: `and`, `or`, `not`, and `@supports selector(...)`.
- ✓Generates progressive enhancement pattern (Baseline fallback first, Enhanced rules inside `@supports`).
- ✓100% Client-Side memory execution.
- ✓1-Click Copy `@supports` block.
Key Terminology & Definitions
`@supports` (Feature Query)
A conditional CSS at-rule that applies style rules only if the user agent supports the specified CSS property-value pairs or selector syntax.
Progressive Enhancement
A web design strategy that emphasizes core content and basic functionality first, adding advanced visual enhancements when supported by the browser.