The updated code you created above worked perfectly. Thanks.

I used the code above for the sticky header on mobile and it works. Problem I am having is that the top portion of content from each page is now hidden under the menu. Any way to fix this?

I am having an issue with the theme in Chrome on mobile. When in Chrome (works fine is safari) the phone numbers are not selectable to activate the Call feature. My site link is texas.smartstartinc.com.