Get the code here: https://divilife.com/how-to-make-to-your-divi-4-0-header-fixed-or-sticky/
The most common question with Divi 4.0 custom headers is "How can I make my header sticky?"
We answered this question and have made two tutorials:
1) How to Make Your Entire Header Fixed
2) How to Make only Part of Your Header Sticky (THIS VIDEO)
Both tutorials can be found here: https://divilife.com/how-to-make-to-your-divi-4-0-header-fixed-or-sticky/