Can you clarify what elements you are talking about as I see no other overlaps. A screenshot would help.
Your site hasn’t updated yet so i can’t tell if you have added something incorrectly.
I do notice that the images inside #htmlcontent_top are dropped down below the main left image. This is because you have made the element 33% wide but there is not 33% of space available. Why did you not use the bootstrap columns as you were supposed to when using boostrap? You could fix the drop by reducing the width to say 31% but the correct answer would be to place each content in a proper bootstrap column because that’s why you are using bootstrap
I’m having a hard time understanding what you want
It would have no effect on anything else on that page as the code you adjusted was on the id of #sb-container of which there can only be one. It will not affect anything else except #sb-container and will raise its z-index above everything else (assuming you don’t trump it somewhere else).
I think we must be talking at cross purposes.
As an aside you could have reduced the z-index on your header instead and as long as you made it below 999 then the popup would show. At the moment your header in global.css has a z-index of 5003:
#header{z-index:5003;}
You could just reduce that below the original z-index of the popup which was 999.
I don’t see any popups in that screenshot but I do see the right column images dropping below the left column images as I already explained and detailed.
These are working urls for what?
They don’t show the images from your screenshot so we can’t compare the dropped images if that was what they were meant to show. Also in those urls the popups are working because you have not given the header a higher z-index as in your initial example.