Background image on mobile

Hi there,

I have a problem with displaying a site on mobile. https://gsmue.literaturwerkstatt-witt.de/firmenchronik/

If I open this site on a mobile device, the text is cutted in a half and if I zoom out, a background image is shown on the right side and the header doesn’t fit the screen. How can I fix that?

Best regards

The page I need help with: [log in to see the link]