HarmonyOS system fonts can support stepless change of word weight and arbitrary adjustment of font thickness. You can enter my category column in the theme and choose to reapply any theme to restore the font to normal. If it hasn't been solved, please try to restore all the settings: enter the phone settings, search and restore all the settings, and follow the on-screen prompts to complete the operation. Restoring all settings won't cause your data loss, but it may lead to a messy desktop layout. For example, the widget on the desktop will disappear, and the application that comes with the system will be restored to the default location.