Floating Button

Elevated floating control for the single most important action on a screen.

Rounded-square icon-only by default with elevated surface styling. Pin to a viewport corner with FloatingButtonConfig::fixed. Set config.variant to FloatingButtonVariant::Circular for a full circle, or FloatingButtonVariant::Extended for icon plus label with the same rounded-square corners.

• One primary action that should stay visible above page content - Back-to-top and similar floating affordances built on the same base

• Provide an icon or extended label via children.
• Set aria_label for icon-only buttons.
• Use config.fixed(right, bottom) when the button should float on the viewport.