Fixed parser/tests

packages/mermaid/src/diagrams/class/classDb.ts

@@ -215,7 +215,7 @@ export const cleanupLabel = function (label: string) {
 };
 
 /**
- * Called by parser when a special node is found, e.g. a clickable element.
+ * Called by parser when assigning cssClass to a class
  *
  * @param ids - Comma separated list of ids
  * @param className - Class to add

packages/mermaid/src/diagrams/class/classDiagram.spec.ts

@@ -409,6 +409,7 @@ class C13["With Città foreign language"]
             },
           ],
           "methods": [],
+          "styles": [],
           "type": "",
         }
       `);

packages/mermaid/src/diagrams/class/parser/classDiagram.jison

@@ -377,7 +377,7 @@ styleStatement
     ;
 
 cssClassStatement
-    : CSSCLASS STR stylesOpt                            {yy.setCssClass($2, $3);}
+    : CSSCLASS STR ALPHA                            {yy.setCssClass($2, $3);}
     ;
 
 stylesOpt