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property-no-unknown

Disallow unknown properties.

a { height: 100%; }
/** ↑
 * This property */

This rule considers properties defined in the CSS Specifications and browser specific properties to be known.

This rule ignores:

  • variables ($sass, @less, --custom-property)
  • vendor-prefixed properties (e.g., -moz-align-self, -webkit-align-self)

Use option checkPrefixed described below to turn on checking of vendor-prefixed properties.

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

Options​

true​

The following patterns are considered problems:

a {
  colr: blue;
}
a {
  my-property: 1;
}

The following patterns are not considered problems:

a {
  color: green;
}
a {
  fill: black;
}
a {
  -moz-align-self: center;
}
a {
  -webkit-align-self: center;
}
a {
  align-self: center;
}

Optional secondary options​

ignoreProperties: ["/regex/", /regex/, "string"]​

Given:

["/^my-/", "custom"]

The following patterns are not considered problems:

a {
  my-property: 10px;
}
a {
  my-other-property: 10px;
}
a {
  custom: 10px;
}

ignoreSelectors: ["/regex/", /regex/, "string"]​

Skips checking properties of the given selectors against this rule.

Given:

[":root"]

The following patterns are not considered problems:

:root {
  my-property: blue;
}

ignoreAtRules: ["/regex/", /regex/, "string"]​

Ignores properties nested within specified at-rules.

Given:

["supports"]

The following patterns are not considered problems:

@supports (display: grid) {
  a {
    my-property: 1;
  }
}

checkPrefixed: true | false (default: false)​

If true, this rule will check vendor-prefixed properties.

For example with true:

The following patterns are not considered problems:

a {
  -webkit-overflow-scrolling: auto;
}
a {
  -moz-box-flex: 0;
}

The following patterns are considered problems:

a {
  -moz-align-self: center;
}
a {
  -moz-overflow-scrolling: center;
}