/
^(?=([A-Za-z0-9]|[^\x00-\x7F])([A-Za-z0-9@._%+-]|[^\x00-\x7F]){5,253}$)([A-Za-z0-9._%+-]|[^\x00-\x7F]){1,64}@(?:(?=([A-Za-z0-9-]|[^\x00-\x7F]){1,63}\.)([A-Za-z0-9]|[^\x00-\x7F])+(?:-([A-Za-z0-9]|[^\x00-\x7F])+)*\.){1,8}([A-Za-z]|[^\x00-\x7F]){2,63}$
/
gm