The HTMLStyleElement.type
read-only property returns the type of the current style.
For Gecko, the type is most often given as "text/css." From the W3C spec on CSS: "The expectation is that binding-specific casting methods can be used to cast down from an instance of the CSSRule interface to the specific derived interface implied by the type."
Syntax
string = style.type;
Example
if (newStyle.type != "text/css"){ // not supported! warnCSS(); }