burger buttons with different styles dont look professional

Hello support,
I have been using ENFOLD for a long time. Thanks for such good theme.
I use the main menu at header and sub menu over full width.
Everything is ok for the desktop view. However, the menus in the mobile view are changed to the burger button. Since the sub menu is attached directly to the header, you can see two different burger icons. It doesn’t look very professional.
See link.
–> https://erlogroup.de/downloads/burger%20styles%20different.jpg
Is it possible to make the burger icon of the submenus identical to the main menu burger icon?
Thanks in advance for your help.
Best regards Jens