add doc

packages/codemirror/codemirror.mjs

@@ -355,4 +355,11 @@ function s4() {
     .substring(1);
 }
 
+/**
+ * Overrides the css of highlighted events. Make sure to use single quotes!
+ * @name markcss
+ * @example
+ * note("c a f e")
+ * .markcss('text-decoration:underline')
+ */
 export const markcss = registerControl('markcss');

website/src/pages/learn/visual-feedback.mdx

@@ -98,3 +98,7 @@ What follows is the API doc of all the options you can pass:
 ## Pitchwheel
 
 <JsDoc client:idle name="pitchwheel" h={0} />
+
+## markcss
+
+<JsDoc client:idle name="markcss" h={0} />