If you are experiencing problems with closing the Bootstrap modal and returning to the top of the page, the following code modification can help.
<a class="modal-button" data-toggle="modal" data-target=".brand-story" href="">
<img class="lazyload play-movie" data-src="renew/ img/play-movie.svg" alt="BRAND STORY PLAY MOVIE">
</a>The problem was that .play-movie had position: absolute set. We solved that by setting position: absolute to .modal-button.
The specific cause is unknown, but I hope this solution helps.