Customize landing page template

Hello, I’m a marketer with limited experience in dev work with HS. Hoping my inquiry is a simple one. BTW, I’m working with a copy of our active Landing Page template.

  1. I’d like to remove the “global” landing page header, which currently has a white background with a centered logo. This also seems to be locked and uneditable
  2. I’d like to float a white container over a section that contains an image background. See reference.