Issue:
The "Back-to-Top" button and Navbar sometimes disappears and doesn't reappear when scrolling, even though the conditions are met.
Task:
Fix the Bug:
Remove the randomness and ensure that the "Back-to-Top" button always appears when window.scrollY >= 100 and disappears otherwise.
Hint:
Focus on ensuring that the condition is consistent and does not depend on non determined factors.
Look in Script.js