Slider is not shown correctly on Safari

I recognized a few days ago that my slider is not working well on Safari, because it has the double size of the image. I tried it with different browsers (Chrome, Mozilla and Edge) and the slider was shown correctly. Here is my link: http://www.worldonabudget.de/

There is also a problem with the images in this article: http://www.worldonabudget.de/gechillt-durch-kuba-teil2/ You can not see them, when you are using Safari. Again, there are no problems with other browsers.

Is there any solution to fix it?