WebStorm integrates with Stylelint so you can inspect your CSS code from inside the IDE. Stylelint wakes up automatically when you edit a CSS file and highlights the detected problems. To view the description of a problem in an information popup, hover the mouse pointer over a stripe in the Validation sidebar. To examine errors and apply suggested quick fixes, press Alt+Enter.
In the embedded Terminal (Alt+F12), type:
npm install -g stylelint
Activating and configuring Stylelint
In the Settings/Preferences dialog (Ctrl+Alt+S), go to Languages and Frameworks | Style Sheets | Stylelint.
On the Stylelint page that opens, select the Enable checkbox to activate Stylelint. After that the controls in the dialog become available.
In the Stylelint Package field, specify the location of the
stylelintpackage installed globally or in the current project.