I have an issue with my header. I have made it on the Master Page and there are no issues whatsoever when I am in Design mode. When I go to preview my website online or in the Preview mode, items in the Header screw up. I understand this is something to do with Pinning but I need to pin the header as I want to keep the header static while scrolling. Images below.
As you can see, my logo changes size on the preview (this also happens when I upload the website). This is actually the most tame way it resizes, other times it can completely resize and change position drastically. Please say if I'm not quite explaining the issue properly.
If I understand correct, you are wanting that all the objects in your site remain the exact same size and proportion as you see them in design mode correct?
In that case I must tell you that being a responsive design you may see a difference in design and your browser, because you design may not alight 100% correctly with your browser size.
This thread should help you with the same - muse design differs from preview
What is the Zoom setting in your browsers? It should be at normal (100%) or Ctrl+0 (zero). See screenshot from Chrome.