A small change that would make implementing styles for elements with background colours a bit easier. It would match the From<T> for Option<T> impl that you can already use for fields that are Option<Color> (like text_color).

Before:

Style {
    background_color: Some(Color::BLACK.into()),
    text_color: Color::WHITE.into(),
    ..Default::default()
}

After:

It will be nice to have style options for MsgBox: option to define class, different mods for each button (right now we can define mod but it is the same for both buttons). Also, it will be great to add icons to the MsgBox buttons (button consistency). Thanks!