1. The "hanging" sticky header let your main menu and logo to always be at the top of the screen, automatically following when you scroll.
2. The transparent sticky header can be enabled/disabled from the option Sticky Header Behaviour - found in the local page's Vamtam options below the text editor.
Please note that this option only works with the standard header layout seen on the demo. If you change the layout from Appearance > Customize > Header > Header Layout, it will be automatically disabled.
Please note that the option "Sticky Header" found in Appearance > Customize > Header > Sticky Header must be "ON" in order to have transparent header working.