Jumbotronheader - Imagelogo and menu not mobile-responsive

Hello!

Already I got good advice in this forum, thanks in advantage for your help :slight_smile:

I have problems resizing the header-logo on my site lenguadefuego.com
I use the jumbotron-header and managed to make it responsive with

@media only screen and (max-width: 768px) {
#header {
background-attachment: initial !important;
}
#header .bottom-header h2 {
font-size:66px;
}
}

Still the header-text (which I made an image) is not responsive, and also the menu, which is just not accessible on mobile devices because its white text on white background (on desktop pc its readable, because the headerimage is black…).
I already tried different codes, which probably dont work, because they make text mobile-responsive, but not images…

Thanks!