at-charset-rule-no-invalid

Disallow invalid @charset rules.

    @charset "utf-8";
/** ↑
 * This @charset rule */

Use this rule to avoid falling back to another encoding. Browsers ignore an invalid @charset and decode the stylesheet with the referring document's encoding or UTF-8.

The @charset rule is not an at-rule. It's a byte sequence that browsers look for at the very start of a stylesheet, as defined in the CSS Syntax Level 3 specification.

It must be written as @charset, followed by a single space, followed by the encoding label in double quotes, followed by a semicolon.

It must also be the first thing in the stylesheet, and it has no effect when the file starts with a byte order mark, as the mark takes precedence over it.

warning

This rule is only appropriate for CSS files. You should not turn it on for CSS-like languages, such as SCSS or Less, or for CSS embedded in another language, such as HTML.

This rule supports 1 message argument: the reason the @charset rule is invalid.

Options

true

{
  "at-charset-rule-no-invalid": true
}

The following patterns are considered problems:

@charset 'utf-8';

@CHARSET "utf-8";

@charset  "utf-8";

@charset "utf-8" ;

/* foo */
@charset "utf-8";

The following patterns are not considered problems:

@charset "utf-8";

@charset "utf-8";
/* foo */