# custom-property-pattern Specify a pattern for custom properties. ```css a { --foo-: 1px; } /** ↑ * The pattern of this */ ``` ## Options `regex|string` A string will be translated into a RegExp like so `new RegExp(yourString)` — so be sure to escape properly. Given the string: ```js "foo-.+" ``` The following patterns are considered warnings: ```css :root { --boo-bar: 0; } ``` The following patterns are *not* considered warnings: ```css :root { --foo-bar: 0; } ```