The animation is frozen on Safari

The animation is frozen in Safari, while it works on Chrome.

On iPad animation does not work at all on both Safari and Chrome.

I do not know if it is bug or there is somthing wrong with Safari and iPad.

Please help me.

Here is a link to problematic page: http://давайте-жить-по-совести.рф/Slavic%20language/Начатокъ.html

P.s. in Edge Animator awrything works.