Validate CSS structure and detect unmatched blocks, malformed declarations, duplicate properties, invalid hexadecimal colors, and undefined custom-property references. Safe fixes are reported separately.
Validate CSS structure and detect unmatched blocks, malformed declarations, duplicate properties, invalid hexadecimal colors, and undefined custom-property references. Safe fixes are reported separately.
Processing is performed locally. Advanced language edge cases may require a full standards-based parser or project-specific toolchain.
Input:
.card {
color #fff;
padding: 10px;
padding: 12px;
background: #12ZZ99;
}Output: Run the included example to see a real result generated by this tool.Paste the stylesheet and run validation to detect structural and declaration-level problems locally in the browser.
The validator flags malformed declaration segments and can add safe trailing semicolons in safe-fix mode.
Declarations are checked per rule and repeated property names are reported with their selector context.
References using var() are compared with declared custom properties and unresolved names are reported as candidates.
All processing runs in the browser and the page does not need to send the source to a server.
| Module | Purpose |
|---|---|
| Structure | Protect strings and comments before scanning. |
| Processing | Apply the selected conversion, parser, validator, viewer, inspector, checker, or generator logic. |
| Reporting | Return output, status, measured size, lines, and practical notes. |