Remove all this CSS.
That way you won't have the aspect ratio issue you were reporting.
I tried replacing this part with another CSS.
No problems occurred.
However, this issue only occurs on iPad and iPhone, and probably not on android.
I've made a pull request for the rewritten CSS.
I was able to identify the cause of the problem when using FullScreen mode + iPad.
Remove all this CSS. That way you won't have the aspect ratio issue you were reporting. I tried replacing this part with another CSS. No problems occurred. However, this issue only occurs on iPad and iPhone, and probably not on android. I've made a pull request for the rewritten CSS.