How to get rid of header and footer for landing page

Hi there

Super new to this but trying to create a simple landing page. I tried inputting the custom CSS code but to no avail. 

This has got to be simple but I just can't seem to crack it! Please help.

I'm on 7.1

Add this to the header code injection in the page settings - advanced for the page you want to hide the header/footer:

<style>
  .header .header-announcement-bar-wrapper {display:none;}
  #footer-sections {display:none;}
</style>