Allow for saving of theme custom CSS when changing a palette or advanced theme element in the UI

aiserver.py

@@ -8102,6 +8102,10 @@ def UI_2_theme_change(data):
         for key, value in data['theme'].items():
             f.write("\t{}: {};\n".format(key, value.replace(";", "").replace("--", "-")))
         f.write("}")
+        f.write("--------Special Rules from Original Theme---------")
+        for rule in data['special_rules']:
+            f.write(rule)
+            f.write("\n")
     if koboldai_vars.debug:
         print("Theme Saved")