The system allows you to validate the CSS style definitions used on pages against the CSS3 standard (opens in a new tab). The validator checks the styles declared in the head section of the page code.
Inline styles declared as attributes of individual HTML elements are not validated.
To validate a page's CSS:
Warning: During validation, your data is sent to an external 3rd party validation service. If you have sensitive, non‑public content, we recommend using other types of validation.
If the validator finds invalid style definitions, the page displays a list of all detected issues. You can see the following information for each issue:
Notes: