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Specify a list of disallowed property and unit pairs within declarations.

a { width: 100px; }
/** ↑ ↑
* These properties and these units */

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


object: { "unprefixed-property-name": ["array", "of", "units"]|"unit" }

If a property name is surrounded with "/" (e.g. "/^animation/"), it is interpreted as a regular expression. This allows, for example, easy targeting of shorthands: /^animation/ will match animation, animation-duration, animation-timing-function, etc.


"font-size": ["em", "px"],
"/^animation/": "s"

The following patterns are considered problems:

a { font-size: 1em; }
a { animation: animation-name 5s ease; }
a { -webkit-animation: animation-name 5s ease; }
a { animation-duration: 5s; }

The following patterns are not considered problems:

a { font-size: 1.2rem; }
a { height: 100px; }
a { animation: animation-name 500ms ease; }
a { -webkit-animation: animation-name 500ms ease; }
a { animation-duration: 500ms; }