I can not understand why the card is acting like this?

At the bottom of the page there is a card https://sro-mfo.ru/xbrl-page/
The questions on it. Firstly why 1st active is not displayed, only after you click on it.
And the main question about the second tab is "navigation to the ENP and the OSCE" do Not understand where it came from is more empty space(it is just the size of the content of the first card) please help
April 4th 20 at 13:00
1 answer
April 4th 20 at 13:02
Solution
Found the cause. The site uses bootstrap 3. And I did so, Cau like bootstrap 4)

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