at-rule-descriptor-no-unknown

Disallow unknown descriptors for at-rules.

@counter-style foo {
  unknown-descriptor: cyclic;
/**                ↑
 * Descriptors like this */
}

This rule considers descriptors defined in the CSS Specifications, up to and including Editor's Drafts, to be known.

You can filter the CSSTree Syntax Reference to find out what descriptors are known for an at-rule.

This rule is only appropriate for CSS. You should not turn it on for CSS-like languages, such as SCSS or Less.

The message secondary option can accept the arguments of this rule.

This rule checks descriptors within at-rules. To check properties, you can use the property-no-unknown rule.

Prior art:

• stylelint-csstree-validator

Options

true

The following patterns are considered problems:

@counter-style foo {
  unknown-descriptor: cyclic;
}

@property --foo {
  unknown-descriptor: "<color>";
}

The following patterns are not considered problems:

@counter-style foo {
  system: cyclic;
}

@property --foo {
  syntax: "<color>";
}