Dropdown not in correct location when previewing/published

I currently have my dropdown list set at a fixed position - 95px from the top.

When I “open menu” in dropdown settings, it is in the correct location.

However when I preview or publish the site, the dropdown come from the top, not from 95px down.

The strange thing is that if I “open menu” and then preview (with it still open) it shows it 95px from the top.

Is this a bug, or am I doing something wrong?

Here is my link Webflow - BIG DROPDOWN

Many thanks

Here is my site Read-Only: LINK
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