I've been struggling with getting the AppBar component to cover the entire area by default. I've searched through the documentation and scoured Google for a solution, but so far I haven't found one that works.
I also attempted to adjust the spacing in createMuiTheme for my Layout component, which includes the AppBar and {props.children} at the end. Unfortunately, this didn't seem to have any effect.
In summary: I want the app bar and all other components to span the full screen, utilizing the entire space as a flex without any default padding that material-ui seems to be automatically adding.