Sticky header on always for all pages except home page

Creating a demo for a client using Customizr Pro with Modern theme setting.
They want a HUGE header for the home page which scrolls to the sticky header…which we have done.
They also want the sticky header to be the only header on all other pages (no HUGE header).
Contemplating ways to accomplish this without taking a bunch of time. I know PHP, HTML, CSS, Javascript – if anyone has done this before and can show me the way – thank you! I am going to work on this tomorrow if I get an answer myself, I will post it here.
Thank you for your help.

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