The main site works well, but when I look at it in mobile, the main menu is the wrong color and becomes unattached from the top when scrolling. The images also appear to be squished and not retaining the proper ratio. How can I adjust this to be normal?
The menu will only gets unattached on admin view, which means the default WordPress admin bar is causing this issue. If you logout and check your site it will be working fine.
Now about the image issue.
We recommend you to use image of higher resolutions so that the will maintain proper ratio on mobile view as lower quality image with lower resolutions cannot be maintained well in mobile view.