Bootstrap 4 possible compatibility error?

Hello, I am using Brackets as my code editor. I am using their live update feature to see what I am doing and all of that jazz. I am editing all of my website with Bootstrap 4(Thank you to whoever recommended I use it over 3.3.7, I love 4 waaayyy more) anyways, I noticed something and I don't know if this is a bootstrap thing or a Brackets thing but I didn't have this happen when I was using 3.3.7. This is what it looks like with the live feature: Brackets Live

And this is what I get when looking at it through actually opening the HTML file: Opening Image through the file

I do not know why this is happening. Please help!