Styles appear locked?

I want to change the background color of my page but when I go to look at the styles it appears locked and I cannot change it. How can I change the background color, or even add a background image if I wanted to?

If you are referring to the Bootstrap 4 files, yes they are locked for a purpose. We do not allow modifying core framework files.
You can add your own styles as explained here: https://wappler.io/docs/#Using-CSS-Designer