Hey @ErichBoehm. Wow, lot’s of things going on here. But nothing un-fixable.
First of all, rule of thumb: ANYTIME you have a parent div, where you will put more divs and content inside of it, ALWAYS set the width, never leave it to Auto.
I usually always start with a Parent Div set to 100VW (that means no matter the screen size, the width will always be the exact screen size, no more, no less). Obviously I take into account margins so I add padding and so on, but that is a healthy first step. Then, the child div that is also a parent to more content (like a text wrap), I set that one to 100% (or whatever number you need, but never auto). Then inside of that Div, my content can be left to whatever I need it to be.
Those two changes alone will help you improve most of the current layout problems. (check screenshot as an example, here I also removed the margin from the text div I think).
Whenever you have elements that you need to have a set Pixel width, then just make sure the numbers (width+margins or padding) do not exceed the total width of your viewport (I hate math, but we cannot hide from it).
Also, final note in case you did not know (I only figured that out halfway into my first project), when you edit a viewport, the changes all apply to that viewport and the ones below it (If you edit an element’s width in Tablet, the numbers also apply to phone. You can then edit the phone viewport, and the changes will only happen there, without worrying about it change in the desktop or tablet viewport).
So go to your phone viewport and start editing there, it will look almost entirely better. After that, the other issues that need another solution will be clearer.
Hope this helps, cheers!