Click the button or press Space/Enter while focused to toggle the content.
Overview: This panel contains additional information that is hidden by default. Use the button above to reveal it.
Accessibility notes: the button uses aria-expanded and aria-controls to connect it to this content region. The content area has role="region" and aria-labelledby pointing back to the controlling button.
Open by default: This example demonstrates the widget with the content visible initially. The script below will pick up the initial state and animate correctly when toggled.
Resize the window to see the script recalculate the max-height for open panels so transitions remain smooth.