Hello @Tim_Lichti,
In CSS rules there is z-index, which controlling “layering” option of objects. In other words: top layer will have z-index higher than other layers.
In Webflow UI you can find z-index on styling panel under Position settings.
For activate z-index rule you will have to give position: relative to your images and then give z-index to “arrow-image” less than to “screen-image”.
Hope I was able to explain.
Regards,
Anna