The NavIcon (three lines/hamburger) menu icon is, in Split, a .svg file. It’s also white… The most common reasons why it cannot be seen are:-
- You have a menu area with a white background, so the NavIcon is lost in the white.
- Your site may be hosted by a provider who does not support .svg files. Usually this can be overcome easily enough either with an .htaccess tweak or a support email to the provider.
I see that in your image from earlier the menu background is white. Try changing it to another colour and seeing if the NavIcon then appears.