Set these under components.FloatButton in your token file, or pass them to ThemeScope to change one region of the page.
Component Tokens
FloatButton's component tokens, with the values the default theme produces. Set one and it applies to every FloatButton under the provider.
Global Tokens
The global tokens FloatButton reads. Set one under components.FloatButton to change it for FloatButton only, or at the top level to change every component.