maintenance/public/assets/less/fastadmin/.csslintrc

{
  "adjoining-classes": false,
  "box-sizing": false,
  "box-model": false,
  "compatible-vendor-prefixes": false,
  "floats": false,
  "font-sizes": false,
  "gradients": false,
  "important": false,
  "known-properties": false,
  "outline-none": false,
  "qualified-headings": false,
  "regex-selectors": false,
  "shorthand": false,
  "text-indent": false,
  "unique-headings": false,
  "universal-selector": false,
  "unqualified-attributes": false,
  "ids": false,
  "fallback-colors": false,
  "vendor-prefix": false,
  "import": false
}