This is where you set up options that affect the style checker and its output. The CSS checker is now included in all editions, but is limited in the lite edition to important CSS errors only.
The CSS checker is designed to check CSS2 and CSS3. It also checks some proprietary CSS syntax (like Microsoft's scrollbar properties). Many CSS problems will be found by the CSS syntax checker but not all CSS is checked.
•Enable CSS style checking in HTML documents - Check this box to enable CSS style checking in HTML/XHTML documents. This does not affect style checking in CSS documents. This option is enabled by default.
•Check "style" attribute for SVG elements - Check this box to check the value of the "style" attribute for SVG elements (where made possible by the configuration file). If unchecked then the value of the "style" attribute when used with SVG elements will be ignored. This option is enabled by default. (New v17.00)
•Allow underscores in class and ID names - Check this box to allow underscore characters (_) in CSS class and ID names. An errata document to CSS2 allows underscores. Underscores should be well supported in current versions of modern browsers. Old (and considered obsolete by today's standards) browsers like Netscape Navigator 4.x and Opera 5.x and older may ignore any class or ID name that contains underscores, although Internet Explorer 4.x and above allow underscores. We recommended that you uncheck this option only if older (obsolete) browser support is needed. This option is enabled by default. (New v9.00)