Scroll Link to specific tab with Offset header

Hello, I followed the instructions in this post (https://www.ads-software.com/support/topic/how-to-link-to-specific-tab/), everything works fine but the scroll to the tab area is too big, reason why the titles of the tabs are not seen and even the content appears cut off. I think the problem occurs because I have the fixed header. Is there a way to solve this problem?

On the other hand I would also like a smooth scroll effect. I have installed several plugins to achieve this effect but none works. They works in other parts of the Web but not with the links that I have created within the single product and that point to the custom tabs.

I add a link of a small video: https://share.getcloudapp.com/7Kum5nGb

Thanks

Manuel

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