How do I remove the Home and Mobile Menu?

Site URL: https://lettuce-clover-mfwa.squarespace.com/

I am trying to remove the home button and mobile menu from my site as it's a one page only website. Can't seem where to do that in the controls.

Also, I'd like the background of the header to just darken slighlty, say a 90% transparency so that there is some definition behind the logo and the content. Is there a place to do that?

Thanks in advance.

I know that if I use the code injection with this:

<style>
          #header { display: none }
</style>

I can hide the header bar.  But I want to show it, just hide the mobile menu on mobile since this is only a one page site.

Thank you @tuanphan, that worked perfectly, the mobile menu no longer appears on the site.

I went to Settings > Advanced > Code Injection and added it to the <HEADER> section.

One last question, how do I make the just darken slighlty, say a 90% transparency so that there is some definition behind the logo and the content. Is there a place to do that? On the 7.0 interface I believe there was a control for that but I don't see it here.

Thank you!

Oh I got it, I found a nice tutorial here that I used:

https://schwartz-edmisten.com/blog/frosted-glass-header-effect-in-squarespace-71

Thanks!