#selector-attribute-brackets-space-inside

Require a single space or disallow whitespace on the inside of the brackets within attribute selectors.

    [ target=_blank ]
/** ↑               ↑
 * The space inside these two brackets */

#Options

string: "always"|"never"

#"always"

There must always be a single space inside the brackets.

The following patterns are considered violations:

[target] {}
[ target] {}
[target ] {}
[target=_blank] {}
[ target=_blank] {}
[target=_blank ] {}

The following patterns are not considered violations:

[ target ] {}
[ target=_blank ] {}

#"never"

There must never be whitespace on the inside the brackets.

The following patterns are considered violations:

[ target] {}
[target ] {}
[ target ] {}
[ target=_blank] {}
[target=_blank ] {}
[ target=_blank ] {}

The following patterns are not considered violations:

[target] {}
[target=_blank] {}