at-rule-name-space-after
Require a single space after at-rule names.
@media (max-width: 600px) {}
/**   ↑
 * The space after at-rule names */The fix
option can automatically fix all of the problems reported by this
rule.
Options
string: "always"|"always-single-line"
"always"
There must always be a single space after at-rule names.
The following patterns are considered violations:
@charset"UTF-8";@media(min-width: 700px) {}@media  (min-width: 700px) {}@media
(min-width: 700px) {}The following patterns are not considered violations:
@charset "UTF-8";@import url("x.css");@media (min-width: 700px) {}"always-single-line"
There must always be a single space after at-rule names in single-line declaration blocks.
The following patterns are considered violations:
@charset"UTF-8";@media(min-width: 700px) {}@media  (min-width: 700px) {}The following patterns are not considered violations:
@charset "UTF-8";@import url("x.css");@media (min-width: 700px) {}@media
(min-width: 700px) {}@media(min-width: 700px) and
  (orientation: portrait) {}@media
  (min-width: 700px) and
  (orientation: portrait) {}