How do I get the main menu to be transgressed when accessing via a phone or tablet? This menu remains the same, and does not turn into an icon with the three horizontal lines.
Let me see it, please provide a link to the website and I will check it
The link: tplcl.fr
I can clearly see the hamburger menu on the mobile devices: Screenshot by Lightshot ? is your problem already resolved?
what is the resolution of the device? the main menu will jump to the mobile menu under 76 px, you can try it in the desktop browser as well