Specify certain rules as warnings

A linter for CSS code.
More information: <https://github.com/CSSLint/csslint/wiki/Command-line-interface>.
Trick copyright: tl;dr; <https://github.com/tldr-pages/tldr>

csslint --warnings={{box-sizing,selector-max,floats}} {{file.css}}

click the source code to copy install csslint on any operating system with command-not-found.com