Remove menu and footer from only a single page?

Hi, Illdy is a superb template and so flexible allowing lots to be achieved, thank you. I am trying to create a new ‘page’ and hide the nav menu and footer sections ONLY in that page - not globally across the site - so that I can use the page as a non-cluttered landing page. I have tried this approach which has been suggested before:

/Remove menu bar/
.page-id-385 #main-nav {
display: none;

/Remove footer/
.page-id-385 #site-generator {
display: none;

but it does not work. Do you have any other suggestions? Site is

Many thanks, Chris

Hello there,

I hope you are doing well today.

Please go to to Appearance > Customize > Additional CSS and try using this CSS:

.page-id-385 #header .top-header { display: none; }

.page-id-385 #footer {
display: none;

Best Regards,