Troubles Keeping an Image Centered with Different PX dimensions

I am having issues keeping my newsletter graphic centered on every single device screen dimension. How do I fix this? I’ve tried so many things but I’m still struggling. When it’s centered on the desktop, it won’t be centered for different mobile screen viewings.

Few ways to do it

  1. Auto margin applied to the image
  2. 100% width applied to the image
  3. Flexbox + horizontal centering

Probably numerous additional ways too!