Menu location on a small screen monitor size

Hi, i’ve clients that are using small monitor screens, by doing that the menu just disappear from the page.
http://www.nipponsat.com.br/2019

I’ve made a test by decreasing the page window and it really disappear.

And that’s how it should keep looking.

Hi,

You have increased mobile menu button with custom css https://www.screencast.com/t/LD7Y0MSL
https://www.screencast.com/t/LAqh3QsBglk

Set it to 0 and button will appear on smaller screens https://www.screencast.com/t/fZ1zpAxxjg

Best Regards!

but it still desktop, i want the normal menu, not the mobile/tablet version, how can i get it done?
if i change it to “0” the mobile version changes it too
image